Jorge Rios - Academia.edu (original) (raw)

Papers by Jorge Rios

Environmental Science & Technology, 2008

In 2000, 3M Company, the primary global manufacturer, announced a phase-out of perfluorooctanesul... more In 2000, 3M Company, the primary global manufacturer, announced a phase-out of perfluorooctanesulfonyl fluoride (POSF, C 8 F 17 SO 2 F)-based materials after perfluorooctanesulfonate (PFOS, C 8 F 17 SO 3 -) was reported in human populations and wildlife. The purpose of this study was to determine whether PFOS and other polyfluoroalkyl concentrations in plasma samples, collected in 2006 from six American Red Cross adult blood donor centers, have declined compared to nonpaired serum samples from the same locations in 2000-2001. For each location, 100 samples were obtained evenly distributed by age (20-69 years) and sex. Analytes measured, using tandem mass spectrometry, were PFOS, perfluorooctanoate (PFOA), perfluorohexanesulfonate (PFHxS), perfluorobutanesulfonate (PFBS), N-methyl perfluorooctanesulfonamidoacetate (Me-PFOSA-AcOH), and N-ethyl perfluorooctanesulfonamidoacetate (Et-PFOSA-AcOH). The geometric mean plasma concentrations were for PFOS 14.5 ng/mL (95% CI 13.9-15.2), PFOA 3.4 ng/ mL (95% CI 3.3-3.6), and PFHxS 1.5 ng/mL (95% CI 1.4-1.6). The majority of PFBS, Me-PFOSA-AcOH, and Et-PFOSA-AcOH concentrations were less than the lower limit of quantitation. Age-and sex-adjusted geometric means were lower in 2006 (approximately 60% for PFOS, 25% for PFOA, and 30% for PFHxS) than those in 2000-2001. The declines for PFOS and PFHxS are consistent with their serum elimination half-lives and the time since the phase-out of POSF-based materials. The shorter serum elimination half-life for PFOA and its smaller percentage decline than PFOS suggests PFOA concentrations measured in the general population are unlikely to be solely attributed to POSF-based materials. Direct and indirect exposure sources of PFOA could include historic and ongoing electrochemical cell fluorination (ECF) of PFOA, telomer production of PFOA, fluorotelomer-based precursors, and other fluoropolymer production.

American Journal of Cardiology, 1969

1. The time sequence of right atria1 and left atria1 depolarization as a guide to the origin of e... more 1. The time sequence of right atria1 and left atria1 depolarization as a guide to the origin of ectopic atria1 beats was studied in 46 patients with heart disease: in 36 patients after electrical stimulation of known areas of the two atria and in 10 patients with ectopic atria1 rhythms. A direct right atria1 and a bipolar esophageal lead were recorded simultaneously with one or more limb and chest leads on a photographic recorder. A catheter-pacemaker assembly was used for electrical stimulation of the atria.

American Journal of Cardiology, 1965

American Journal of Cardiology, 1989

Environmental Science & Technology, 2008

In 2000, 3M Company, the primary global manufacturer, announced a phase-out of perfluorooctanesul... more In 2000, 3M Company, the primary global manufacturer, announced a phase-out of perfluorooctanesulfonyl fluoride (POSF, C 8 F 17 SO 2 F)-based materials after perfluorooctanesulfonate (PFOS, C 8 F 17 SO 3 -) was reported in human populations and wildlife. The purpose of this study was to determine whether PFOS and other polyfluoroalkyl concentrations in plasma samples, collected in 2006 from six American Red Cross adult blood donor centers, have declined compared to nonpaired serum samples from the same locations in 2000-2001. For each location, 100 samples were obtained evenly distributed by age (20-69 years) and sex. Analytes measured, using tandem mass spectrometry, were PFOS, perfluorooctanoate (PFOA), perfluorohexanesulfonate (PFHxS), perfluorobutanesulfonate (PFBS), N-methyl perfluorooctanesulfonamidoacetate (Me-PFOSA-AcOH), and N-ethyl perfluorooctanesulfonamidoacetate (Et-PFOSA-AcOH). The geometric mean plasma concentrations were for PFOS 14.5 ng/mL (95% CI 13.9-15.2), PFOA 3.4 ng/ mL (95% CI 3.3-3.6), and PFHxS 1.5 ng/mL (95% CI 1.4-1.6). The majority of PFBS, Me-PFOSA-AcOH, and Et-PFOSA-AcOH concentrations were less than the lower limit of quantitation. Age-and sex-adjusted geometric means were lower in 2006 (approximately 60% for PFOS, 25% for PFOA, and 30% for PFHxS) than those in 2000-2001. The declines for PFOS and PFHxS are consistent with their serum elimination half-lives and the time since the phase-out of POSF-based materials. The shorter serum elimination half-life for PFOA and its smaller percentage decline than PFOS suggests PFOA concentrations measured in the general population are unlikely to be solely attributed to POSF-based materials. Direct and indirect exposure sources of PFOA could include historic and ongoing electrochemical cell fluorination (ECF) of PFOA, telomer production of PFOA, fluorotelomer-based precursors, and other fluoropolymer production.

American Journal of Cardiology, 1969

1. The time sequence of right atria1 and left atria1 depolarization as a guide to the origin of e... more 1. The time sequence of right atria1 and left atria1 depolarization as a guide to the origin of ectopic atria1 beats was studied in 46 patients with heart disease: in 36 patients after electrical stimulation of known areas of the two atria and in 10 patients with ectopic atria1 rhythms. A direct right atria1 and a bipolar esophageal lead were recorded simultaneously with one or more limb and chest leads on a photographic recorder. A catheter-pacemaker assembly was used for electrical stimulation of the atria.

American Journal of Cardiology, 1965

American Journal of Cardiology, 1989