Ruchaya Boonyatumanond - Academia.edu (original) (raw)

Papers by Ruchaya Boonyatumanond

Research paper thumbnail of Risk assessment of inhalation exposure to Polychlorinated dibenzo-p-dioxins, dibenzofurans and Dioxin-like PCBs in Ambient Air, Thailand

In order to assess the situation of air quality of Persistent Organic Pollutants (POPs), Polychlo... more In order to assess the situation of air quality of Persistent Organic Pollutants (POPs), Polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and Dioxin-like PCBs (Dl-PCBs) with a total of 29 isomers and their risk assessment were estimated from two hundred ambient air samples in Thailand since 2018–2022. A monitoring program was carried out in Mega-city, industrial area, landfill sites, haze pollution areas, industrial estate areas and National parks that would represent a clean area. The total concentrations of PCDD/Fs and Dioxin-like PCBs in Bangkok area ranged from 0.011–0.17 pg-TEQ/m3 and average total concentration was 0.059 pg-TEQ/m3. The calculation of Daily Inhalation Dose (DID) at an old industrial estate (Bangpoo) for adults weighing about 55–80 kg ranged from 0.12–0.19 pg-TEQ kg− 1day− 1 and the DID in children with ages less than 6 years old ranged from 0.060–0.090 pg-TEQ .kg− 1day− 1. The concentrations of PCDD/Fs detected at Bangpoo industrial estate was about t...

Research paper thumbnail of Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

Environmental Monitoring and Assessment, Mar 17, 2007

A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocr... more A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals (EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines during 1994-1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent of industrialization in these regions. No consistent relationship between concentrations of phenolic EDCs and LABs were found, suggesting that sewage is not a major source of EDCs. Concentrations of PAHs ranged from 11 to 1,133 ng/g-dry, which were categorized as "low to moderate" levels of pollution. The ratio of methylphenanthrenes to phenanthrene (MP/P ratio) was >1.0 in 20 out of 25 locations, indicating extensive input of petrogenic PAHs. This study provides a bench-mark for data on the distribution of anthropogenic contaminants in this region, which is essential in evaluating temporal and spatial variation and effect of future regulatory measures.

Research paper thumbnail of Concentration of Organochlorine Pesticides in the Chao Phraya River, Thailand

Kankyō kagaku, 1996

Water samples from the Chao Phraya River, the main river in Thailand, were collected and analyzed... more Water samples from the Chao Phraya River, the main river in Thailand, were collected and analyzed during 1988-1995. The Organochlorine pesticides such as HCHs, DDTs, aldrin, dieldrin and chlordanes were determined. Aldrin and dieldrin occured frequently in water samples. The medians of concentrations of pesticides were approximately one order of magnitude higher than total HCHs and DDTs. Levels of aldrin were relatively high in the upstream while levels of DDTs were high in the urban area of Bangkok during 1989-1990. p,p'DDE levels were relatively high in 1992. Relatively high levels of endosulfan sulfate were frequently found in lower part of the river in 1995. The trends of the residue level of pesticides found were fluctuated along the river.

Research paper thumbnail of Determination of polycyclic aromatic hydrocarbons in water samples by using high performance liquid chromatography

Research paper thumbnail of Sources and distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments, Thailand

To assess the distribution of polycyclic aromatic hydrocarbons (PAHs) and identifying the main so... more To assess the distribution of polycyclic aromatic hydrocarbons (PAHs) and identifying the main source of the pollutants in coastal, canals, riverine and the upper Gulf of Thailand, surface sediments were collected from urban canals (n = 8), the Chao Phraya River (n = 11), estuarine (n = 9), coastal area (n = 14) and the upper Gulf of Thailand (n = 28) and analyzed for 3-7 rings of PAHs. Sources pollutants and media of transport (ambient air, asphalt, tire, crankcase oil, soot, street dust, and street runoff) were collected from heavy traffic road in Bangkok and rural area. The research finding indicated that PAHs contaminations in Thai sediments as low to moderate. Especially, urban canals were detected at high concentration ranging from 512 to 8399 ng/g (2290 ± 2556 ng/g; n = 8). On the other hand, the coastal areas were detected at low concentration ranging from 6 to 228 ng/g (50 ± 56 ng/g; n = 14). Among the possible sources of PAHs, cluster analysis categorized that, street dust...

Research paper thumbnail of Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

Environmental Monitoring and Assessment, 2007

A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocr... more A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals (EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines during 1994–1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent of industrialization in these regions. No consistent relationship between concentrations of phenoli...

Research paper thumbnail of Distribution of polychlorinated biphenyl (PCBs) in sediment from aquatic environment, Thailand

To assess the status and understand the historical trends of polychlorinated biphenyls (PCBs) in ... more To assess the status and understand the historical trends of polychlorinated biphenyls (PCBs) in Thailand, we collected forty surface sediments and two sediment cores samples from the Chao Phraya River and the Gulf of Thailand during 2004 to 2006. All samples were calculated for dry weight basis. The total PCBs concentrations were calculated from 44 isomers and congeners. 137 Cs was measured to date the sediment cores. The analyses suggested that core GT15 had an appropriate sediment accumulation rate (~1 cm/year) and covered the past 60 years. The results showed the decreasing trend of PCBs concentration in sediment from canals to the river mouth of the Chao Phraya River and to the upper Gulf of Thailand, which ranging from 112 to 933 pg/g, 70 to 217 pg/g, and 128 to 194 pg/g, respectively. The result of PCBs from the sediment cores (GT14 and GT15) ranged from 80-180 pg/g and 200-2200 pg/g, respectively. The dramatic decrease in PCB concentrations around 30 cm (GT15), corresponding...

Research paper thumbnail of Toko A. The concentration of polycyclic aromatic hydrocarbon in surface sediment from canal, river, and coastal area

The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rive... more The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rivers, estuaries and coastal area in Thailand were investigated in 2003. In order to assess the status of the pollutants, thirty-five of sediment samples were collected and analysed from low to high molecular weight (3-7 rings) PAHs by gas chromatography mass spectrometer (GC/MS). Total concentration of PAHs in sediment range is 6-8399 ng g-1(dry weight). The average of total PAHs concentration in sediment samples from canals, rivers, estuaries and coastal area are 2554, 226, 325, and 62 ng g-1(dry weight), respectively. The result indicated that the surface sediment were accumulated the PAHs, especially canal sediments were detected at high concentration range 512 to 8399 ng g-1(dry weight). The composition of PAHs showed the patterns of PAHs and the ratios of methylphenanthrenes/phenanthrene (MP/P ratio) are 0.27-3.10, Flu/Pyr are 0.58-1.45, and Flu/Flu+Pyr ratio are 0.41-0.64, which all ...

Research paper thumbnail of Distribution, sources and historical trend of organic micropollutants in Thailand

Research paper thumbnail of Distribution of Organochlorine Pesticides in the Chao Phraya River, Thailand

Water samples from the Chao Phraya River, the main river in Thailand were collected and analyzed ... more Water samples from the Chao Phraya River, the main river in Thailand were collected and analyzed during 1988–1994. Organochlorine pesticides such as HCHs, DDTs, aldrin, dieldrin and chlordanes were determined. Aldrin and dieldrin had high frequencies of occurrence in water samples. The concentration median of the pesticides was approximately one order of magnitude higher than those of total HCHs and DDTs. Levels of aldrin were relatively high in the upstream while levels of DDTs were high in the urban area of Bangkok during 1989–1990. p,p′-DDE levels were relatively higher in 1992. No clear trends in the levels of pesticides were observed.

Research paper thumbnail of The concentration of polycyclic aromatic hydrocarbon in surface sediment from canal, river, and coastal area in Thailand

The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rive... more The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rivers, estuaries and coastal area in Thailand were investigated in 2003. In order to assess the status of the pollutants, thirty-five of sediment samples were collected and analysed from low to high molecular weight (3-7 rings) PAHs by gas chromatography mass spectrometer (GC/MS). Total concentration of PAHs in sediment range is 6-8399 ng g -1 (dry weight). The average of total PAHs concentration in sediment samples from canals, rivers, estuaries and coastal area are 2554, 226, 325, and 62 ng g -1 (dry weight), respectively. The result indicated that the surface sediment were accumulated the PAHs, especially canal sediments were detected at high concentration range 512 to 8399 ng g -1 (dry weight). The composition of PAHs showed the patterns of PAHs and the ratios of methylphenanthrenes/phenanthrene (MP/P ratio) are 0.27-3.10, Flu/Pyr are 0.58-1.45, and Flu/Flu+Pyr ratio are 0.41-0.64, whic...

Research paper thumbnail of Current Status of Contamination by Persistent Organochlorines in the Lower Chao Phraya River, Thailand

Water Science and Technology

Water and sediment samples collected from the lower Chao Phraya River and a canal along the river... more Water and sediment samples collected from the lower Chao Phraya River and a canal along the river during 1988 - 1991 were analyzed to determine the current status of contamination by organochlorine pesticides, such as HCHs, DDTs, aldrin, dieldrin and chlordanes. Aldrin and dieldrin had high frequencies of occurrence in water samples. The medians of concentrations of these pesticides were approximately one order of magnitude larger than total HCHs and total DDTs. Residue levels of these pesticides varied significantly. Relatively higher levels of aldrin were observed in the upstream; in contrast, residue levels of DDTs were higher in urban area. These phenomena seem to relate to the spraying purpose of these pesticides. Decreasing trends in the residue levels of pesticides during monitoring periods, however, were not observed clearly. Residue levels of organochlorines in the sediment samples were in the order of magnitude of PCBs, DDTs, chlordanes and HCHs.

Research paper thumbnail of Environmental monitoring for POPs in Thailand

Research paper thumbnail of Microplastics in Sediment Cores from Asia and Africa as Indicators of Temporal Trends in Plastic Pollution

Archives of environmental contamination and toxicology, Jan 22, 2017

Microplastics (<5 mm) were extracted from sediment cores collected in Japan, Thailand, Malaysi... more Microplastics (<5 mm) were extracted from sediment cores collected in Japan, Thailand, Malaysia, and South Africa by density separation after hydrogen peroxide treatment to remove biofilms were and identified using FTIR. Carbonyl and vinyl indices were used to avoid counting biopolymers as plastics. Microplastics composed of variety of polymers, including polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethyleneterphthalates (PET), polyethylene-polypropylene copolymer (PEP), and polyacrylates (PAK), were identified in the sediment. We measured microplastics between 315 µm and 5 mm, most of which were in the range 315 µm-1 mm. The abundance of microplastics in surface sediment varied from 100 pieces/kg-dry sediment in a core collected in the Gulf of Thailand to 1900 pieces/kg-dry sediment in a core collected in a canal in Tokyo Bay. A far higher stock of PE and PP composed microplastics in sediment compared with surface water samples collected in a canal in Tokyo Bay s...

Research paper thumbnail of Distribution of polychlorinated biphenyl (PCBs) in sediment from aquatic environment, Thailand

Research paper thumbnail of Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

Research paper thumbnail of Sources of polycyclic aromatic hydrocarbons (PAHs) in street dust in a tropical Asian mega-city, Bangkok, Thailand

Science of The Total Environment, 2007

We collected samples of roadside air, automobile exhaust soot, tires, asphalt, and used engine oi... more We collected samples of roadside air, automobile exhaust soot, tires, asphalt, and used engine oil in a tropical Asian mega-city, Bangkok, Thailand, and analyzed them for polycyclic aromatic hydrocarbons (PAHs) and hopanes. The concentrations and compositions of PAHs and hopanes were utilized to identify the sources of PAHs in street dust, in which high concentrations of PAHs were reported in our previous study. Weight-based concentrations of total PAHs had the following order: gasoline-powered vehicle soot (2600+/-2900 microg/g; n=4)&amp;amp;amp;amp;amp;amp;amp;amp;gt;diesel-powered vehicle soot (115+/-245 microg/g; n=7) approximately roadside aerosols (101+/-35 microg/g; n=5) approximately used engine oil (97+/-65 microg/g; n=4) approximately tire wear particles (82+/-41 microg/g; n=5)&amp;amp;amp;amp;amp;amp;amp;amp;gt;asphalt (2.3+/-1.6 microg/g; n=3)&amp;amp;amp;amp;amp;amp;amp;amp;gt;street dust (1.1+/-0.8 microg/g; n=10). In cluster analysis, all the source materials fell into different clusters from that in which street dust fell, indicating that multiple source materials contribute to PAHs in the street dust. Multiple regression analysis of PAH profiles and diagnostics of hopane compositions identified tire debris as the major contributor of PAHs to street dust, followed by diesel vehicle exhaust.

Research paper thumbnail of Distribution of linear alkylbenzenes (LABs) in riverine and coastal environments in South and Southeast Asia

Water Research, 2004

This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asi... more This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asia during 1998-2003 using linear alkylbenzenes (LABs) as molecular tracers of sewage contamination. Eighty-nine water samples collected from Malaysia, Vietnam, and Japan (Tokyo), and 161 surface sediment samples collected from Tokyo,

Research paper thumbnail of Distribution of linear alkylbenzenes (LABs) in riverine and coastal environments in South and Southeast Asia

Water Research, 2004

This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asi... more This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asia during 1998-2003 using linear alkylbenzenes (LABs) as molecular tracers of sewage contamination. Eighty-nine water samples collected from Malaysia, Vietnam, and Japan (Tokyo), and 161 surface sediment samples collected from Tokyo,

Research paper thumbnail of Transport and release of chemicals from plastics to the environment and to wildlife

Philosophical Transactions of the Royal Society B: Biological Sciences, 2009

Plastics debris in the marine environment, including resin pellets, fragments and microscopic pla... more Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain organic contaminants, including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2′-bis( p- chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concentrations from sub ng g –1 to µg g –1 . Some of these compounds are added during plastics manufacture, while others adsorb from the surrounding seawater. Concentrations of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calculations and experimental observations consistently show that polyethylene accumulates more organic contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a mathematical model using equilibrium partitioning and experimental data have demonstrated the...

Research paper thumbnail of Risk assessment of inhalation exposure to Polychlorinated dibenzo-p-dioxins, dibenzofurans and Dioxin-like PCBs in Ambient Air, Thailand

In order to assess the situation of air quality of Persistent Organic Pollutants (POPs), Polychlo... more In order to assess the situation of air quality of Persistent Organic Pollutants (POPs), Polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and Dioxin-like PCBs (Dl-PCBs) with a total of 29 isomers and their risk assessment were estimated from two hundred ambient air samples in Thailand since 2018–2022. A monitoring program was carried out in Mega-city, industrial area, landfill sites, haze pollution areas, industrial estate areas and National parks that would represent a clean area. The total concentrations of PCDD/Fs and Dioxin-like PCBs in Bangkok area ranged from 0.011–0.17 pg-TEQ/m3 and average total concentration was 0.059 pg-TEQ/m3. The calculation of Daily Inhalation Dose (DID) at an old industrial estate (Bangpoo) for adults weighing about 55–80 kg ranged from 0.12–0.19 pg-TEQ kg− 1day− 1 and the DID in children with ages less than 6 years old ranged from 0.060–0.090 pg-TEQ .kg− 1day− 1. The concentrations of PCDD/Fs detected at Bangpoo industrial estate was about t...

Research paper thumbnail of Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

Environmental Monitoring and Assessment, Mar 17, 2007

A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocr... more A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals (EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines during 1994-1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent of industrialization in these regions. No consistent relationship between concentrations of phenolic EDCs and LABs were found, suggesting that sewage is not a major source of EDCs. Concentrations of PAHs ranged from 11 to 1,133 ng/g-dry, which were categorized as &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;low to moderate&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; levels of pollution. The ratio of methylphenanthrenes to phenanthrene (MP/P ratio) was &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;1.0 in 20 out of 25 locations, indicating extensive input of petrogenic PAHs. This study provides a bench-mark for data on the distribution of anthropogenic contaminants in this region, which is essential in evaluating temporal and spatial variation and effect of future regulatory measures.

Research paper thumbnail of Concentration of Organochlorine Pesticides in the Chao Phraya River, Thailand

Kankyō kagaku, 1996

Water samples from the Chao Phraya River, the main river in Thailand, were collected and analyzed... more Water samples from the Chao Phraya River, the main river in Thailand, were collected and analyzed during 1988-1995. The Organochlorine pesticides such as HCHs, DDTs, aldrin, dieldrin and chlordanes were determined. Aldrin and dieldrin occured frequently in water samples. The medians of concentrations of pesticides were approximately one order of magnitude higher than total HCHs and DDTs. Levels of aldrin were relatively high in the upstream while levels of DDTs were high in the urban area of Bangkok during 1989-1990. p,p'DDE levels were relatively high in 1992. Relatively high levels of endosulfan sulfate were frequently found in lower part of the river in 1995. The trends of the residue level of pesticides found were fluctuated along the river.

Research paper thumbnail of Determination of polycyclic aromatic hydrocarbons in water samples by using high performance liquid chromatography

Research paper thumbnail of Sources and distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments, Thailand

To assess the distribution of polycyclic aromatic hydrocarbons (PAHs) and identifying the main so... more To assess the distribution of polycyclic aromatic hydrocarbons (PAHs) and identifying the main source of the pollutants in coastal, canals, riverine and the upper Gulf of Thailand, surface sediments were collected from urban canals (n = 8), the Chao Phraya River (n = 11), estuarine (n = 9), coastal area (n = 14) and the upper Gulf of Thailand (n = 28) and analyzed for 3-7 rings of PAHs. Sources pollutants and media of transport (ambient air, asphalt, tire, crankcase oil, soot, street dust, and street runoff) were collected from heavy traffic road in Bangkok and rural area. The research finding indicated that PAHs contaminations in Thai sediments as low to moderate. Especially, urban canals were detected at high concentration ranging from 512 to 8399 ng/g (2290 ± 2556 ng/g; n = 8). On the other hand, the coastal areas were detected at low concentration ranging from 6 to 228 ng/g (50 ± 56 ng/g; n = 14). Among the possible sources of PAHs, cluster analysis categorized that, street dust...

Research paper thumbnail of Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

Environmental Monitoring and Assessment, 2007

A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocr... more A comprehensive monitoring survey for polycyclic aromatic hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals (EDCs) utilizing mussels as sentinel organisms was conducted in South and Southeast Asia as a part of the Asian Mussel Watch project. Green mussel (Perna viridis) samples collected from a total of 48 locations in India, Indonesia, Singapore, Malaysia, Thailand, Cambodia, Vietnam, and the Philippines during 1994–1999 were analyzed for PAHs, EDCs including nonylphenol (NP), octylphenol (OP) and bisphenol A (BPA), and linear alkylbenzenes (LABs) as molecular markers for sewage. Concentrations of NP ranged from 18 to 643 ng/g-dry tissue. The highest levels of NP in Malaysia, Singapore, the Philippines, and Indonesia were comparable to those observed in Tokyo Bay. Elevated concentrations of EDCs were not observed in Vietnam and Cambodia, probably due to the lower extent of industrialization in these regions. No consistent relationship between concentrations of phenoli...

Research paper thumbnail of Distribution of polychlorinated biphenyl (PCBs) in sediment from aquatic environment, Thailand

To assess the status and understand the historical trends of polychlorinated biphenyls (PCBs) in ... more To assess the status and understand the historical trends of polychlorinated biphenyls (PCBs) in Thailand, we collected forty surface sediments and two sediment cores samples from the Chao Phraya River and the Gulf of Thailand during 2004 to 2006. All samples were calculated for dry weight basis. The total PCBs concentrations were calculated from 44 isomers and congeners. 137 Cs was measured to date the sediment cores. The analyses suggested that core GT15 had an appropriate sediment accumulation rate (~1 cm/year) and covered the past 60 years. The results showed the decreasing trend of PCBs concentration in sediment from canals to the river mouth of the Chao Phraya River and to the upper Gulf of Thailand, which ranging from 112 to 933 pg/g, 70 to 217 pg/g, and 128 to 194 pg/g, respectively. The result of PCBs from the sediment cores (GT14 and GT15) ranged from 80-180 pg/g and 200-2200 pg/g, respectively. The dramatic decrease in PCB concentrations around 30 cm (GT15), corresponding...

Research paper thumbnail of Toko A. The concentration of polycyclic aromatic hydrocarbon in surface sediment from canal, river, and coastal area

The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rive... more The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rivers, estuaries and coastal area in Thailand were investigated in 2003. In order to assess the status of the pollutants, thirty-five of sediment samples were collected and analysed from low to high molecular weight (3-7 rings) PAHs by gas chromatography mass spectrometer (GC/MS). Total concentration of PAHs in sediment range is 6-8399 ng g-1(dry weight). The average of total PAHs concentration in sediment samples from canals, rivers, estuaries and coastal area are 2554, 226, 325, and 62 ng g-1(dry weight), respectively. The result indicated that the surface sediment were accumulated the PAHs, especially canal sediments were detected at high concentration range 512 to 8399 ng g-1(dry weight). The composition of PAHs showed the patterns of PAHs and the ratios of methylphenanthrenes/phenanthrene (MP/P ratio) are 0.27-3.10, Flu/Pyr are 0.58-1.45, and Flu/Flu+Pyr ratio are 0.41-0.64, which all ...

Research paper thumbnail of Distribution, sources and historical trend of organic micropollutants in Thailand

Research paper thumbnail of Distribution of Organochlorine Pesticides in the Chao Phraya River, Thailand

Water samples from the Chao Phraya River, the main river in Thailand were collected and analyzed ... more Water samples from the Chao Phraya River, the main river in Thailand were collected and analyzed during 1988–1994. Organochlorine pesticides such as HCHs, DDTs, aldrin, dieldrin and chlordanes were determined. Aldrin and dieldrin had high frequencies of occurrence in water samples. The concentration median of the pesticides was approximately one order of magnitude higher than those of total HCHs and DDTs. Levels of aldrin were relatively high in the upstream while levels of DDTs were high in the urban area of Bangkok during 1989–1990. p,p′-DDE levels were relatively higher in 1992. No clear trends in the levels of pesticides were observed.

Research paper thumbnail of The concentration of polycyclic aromatic hydrocarbon in surface sediment from canal, river, and coastal area in Thailand

The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rive... more The concentration of polycyclic aromatic hydrocarbon (PAHs) of surface sediment from canals, rivers, estuaries and coastal area in Thailand were investigated in 2003. In order to assess the status of the pollutants, thirty-five of sediment samples were collected and analysed from low to high molecular weight (3-7 rings) PAHs by gas chromatography mass spectrometer (GC/MS). Total concentration of PAHs in sediment range is 6-8399 ng g -1 (dry weight). The average of total PAHs concentration in sediment samples from canals, rivers, estuaries and coastal area are 2554, 226, 325, and 62 ng g -1 (dry weight), respectively. The result indicated that the surface sediment were accumulated the PAHs, especially canal sediments were detected at high concentration range 512 to 8399 ng g -1 (dry weight). The composition of PAHs showed the patterns of PAHs and the ratios of methylphenanthrenes/phenanthrene (MP/P ratio) are 0.27-3.10, Flu/Pyr are 0.58-1.45, and Flu/Flu+Pyr ratio are 0.41-0.64, whic...

Research paper thumbnail of Current Status of Contamination by Persistent Organochlorines in the Lower Chao Phraya River, Thailand

Water Science and Technology

Water and sediment samples collected from the lower Chao Phraya River and a canal along the river... more Water and sediment samples collected from the lower Chao Phraya River and a canal along the river during 1988 - 1991 were analyzed to determine the current status of contamination by organochlorine pesticides, such as HCHs, DDTs, aldrin, dieldrin and chlordanes. Aldrin and dieldrin had high frequencies of occurrence in water samples. The medians of concentrations of these pesticides were approximately one order of magnitude larger than total HCHs and total DDTs. Residue levels of these pesticides varied significantly. Relatively higher levels of aldrin were observed in the upstream; in contrast, residue levels of DDTs were higher in urban area. These phenomena seem to relate to the spraying purpose of these pesticides. Decreasing trends in the residue levels of pesticides during monitoring periods, however, were not observed clearly. Residue levels of organochlorines in the sediment samples were in the order of magnitude of PCBs, DDTs, chlordanes and HCHs.

Research paper thumbnail of Environmental monitoring for POPs in Thailand

Research paper thumbnail of Microplastics in Sediment Cores from Asia and Africa as Indicators of Temporal Trends in Plastic Pollution

Archives of environmental contamination and toxicology, Jan 22, 2017

Microplastics (<5 mm) were extracted from sediment cores collected in Japan, Thailand, Malaysi... more Microplastics (<5 mm) were extracted from sediment cores collected in Japan, Thailand, Malaysia, and South Africa by density separation after hydrogen peroxide treatment to remove biofilms were and identified using FTIR. Carbonyl and vinyl indices were used to avoid counting biopolymers as plastics. Microplastics composed of variety of polymers, including polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethyleneterphthalates (PET), polyethylene-polypropylene copolymer (PEP), and polyacrylates (PAK), were identified in the sediment. We measured microplastics between 315 µm and 5 mm, most of which were in the range 315 µm-1 mm. The abundance of microplastics in surface sediment varied from 100 pieces/kg-dry sediment in a core collected in the Gulf of Thailand to 1900 pieces/kg-dry sediment in a core collected in a canal in Tokyo Bay. A far higher stock of PE and PP composed microplastics in sediment compared with surface water samples collected in a canal in Tokyo Bay s...

Research paper thumbnail of Distribution of polychlorinated biphenyl (PCBs) in sediment from aquatic environment, Thailand

Research paper thumbnail of Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) and phenolic endocrine disrupting chemicals in South and Southeast Asian mussels

Research paper thumbnail of Sources of polycyclic aromatic hydrocarbons (PAHs) in street dust in a tropical Asian mega-city, Bangkok, Thailand

Science of The Total Environment, 2007

We collected samples of roadside air, automobile exhaust soot, tires, asphalt, and used engine oi... more We collected samples of roadside air, automobile exhaust soot, tires, asphalt, and used engine oil in a tropical Asian mega-city, Bangkok, Thailand, and analyzed them for polycyclic aromatic hydrocarbons (PAHs) and hopanes. The concentrations and compositions of PAHs and hopanes were utilized to identify the sources of PAHs in street dust, in which high concentrations of PAHs were reported in our previous study. Weight-based concentrations of total PAHs had the following order: gasoline-powered vehicle soot (2600+/-2900 microg/g; n=4)&amp;amp;amp;amp;amp;amp;amp;amp;gt;diesel-powered vehicle soot (115+/-245 microg/g; n=7) approximately roadside aerosols (101+/-35 microg/g; n=5) approximately used engine oil (97+/-65 microg/g; n=4) approximately tire wear particles (82+/-41 microg/g; n=5)&amp;amp;amp;amp;amp;amp;amp;amp;gt;asphalt (2.3+/-1.6 microg/g; n=3)&amp;amp;amp;amp;amp;amp;amp;amp;gt;street dust (1.1+/-0.8 microg/g; n=10). In cluster analysis, all the source materials fell into different clusters from that in which street dust fell, indicating that multiple source materials contribute to PAHs in the street dust. Multiple regression analysis of PAH profiles and diagnostics of hopane compositions identified tire debris as the major contributor of PAHs to street dust, followed by diesel vehicle exhaust.

Research paper thumbnail of Distribution of linear alkylbenzenes (LABs) in riverine and coastal environments in South and Southeast Asia

Water Research, 2004

This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asi... more This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asia during 1998-2003 using linear alkylbenzenes (LABs) as molecular tracers of sewage contamination. Eighty-nine water samples collected from Malaysia, Vietnam, and Japan (Tokyo), and 161 surface sediment samples collected from Tokyo,

Research paper thumbnail of Distribution of linear alkylbenzenes (LABs) in riverine and coastal environments in South and Southeast Asia

Water Research, 2004

This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asi... more This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asia during 1998-2003 using linear alkylbenzenes (LABs) as molecular tracers of sewage contamination. Eighty-nine water samples collected from Malaysia, Vietnam, and Japan (Tokyo), and 161 surface sediment samples collected from Tokyo,

Research paper thumbnail of Transport and release of chemicals from plastics to the environment and to wildlife

Philosophical Transactions of the Royal Society B: Biological Sciences, 2009

Plastics debris in the marine environment, including resin pellets, fragments and microscopic pla... more Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain organic contaminants, including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2′-bis( p- chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concentrations from sub ng g –1 to µg g –1 . Some of these compounds are added during plastics manufacture, while others adsorb from the surrounding seawater. Concentrations of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calculations and experimental observations consistently show that polyethylene accumulates more organic contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a mathematical model using equilibrium partitioning and experimental data have demonstrated the...