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1.
Environ Sci Technol ; 47(23): 13266-75, 2013.
Article in English | MEDLINE | ID: mdl-24187954

ABSTRACT

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were previously detected (≥ 4 ng/L) in 65% and 30%, respectively, of 23 New Jersey (NJ) public drinking water systems (PWS) sampled in 2006. We now report on a 2009 study of the occurrence of PFOA, PFOS, and eight other perfluorinated compounds (PFCs) in raw water samples from 30 intakes (18 groundwater and 12 surface water) from 29 additional NJ PWS. Between 1 and 8 PFCs were detected (≥ 5 ng/L) in 21 (70%) of 30 PWS samples at total PFC concentrations of 5-174 ng/L. Although PFOA was the most commonly detected PFC (57% of samples) and was found at the highest maximum concentration (100 ng/L), some of the higher levels of other PFCs were at sites with little or no PFOA. Perfluorononanoic acid was detected more frequently (30%) and at higher concentrations (up to 96 ng/L) than in raw or finished drinking water elsewhere, and it was found at several sites as the sole or predominant PFC, a pattern not reported in other drinking water studies. PFOS, perfluoropentanoic acid, and perfluorohexanoic acid were each detected in more than 20% of samples, while perfluoroheptanoic acid, perfluorobutane sulfonic acid, and perfluorohexane sulfonic acid were detected less frequently. Perfluorobutanoic acid was found only once (6 ng/L), and perfluorodecanoic acid was not detected. Total PFCs were highest in two reservoirs near an airfield; these were also the only sites with total perfluorosulfonic acids higher than total perfluorocarboxylic acids (PFCAs). PFC levels in raw and finished water from the same source were similar at those sites where both were tested. Five wells of two additional NJ PWS known to be contaminated with PFOA were also each sampled 4-9 times in 2010-13 for nine of the same PFCs. Total PFCs (almost completely PFCAs) at one of these PWS located near an industrial source of PFCs were higher than in any other PWS tested (up to 330 ng/L). These results show that multiple PFCs are commonly found in raw water from NJ PWS. Future work is needed to develop approaches for assessing the potential human health risks of exposure to mixtures of PFCs found in drinking water and other environmental media.


Subject(s)
Drinking Water/chemistry , Environmental Monitoring/statistics & numerical data , Fluorocarbons/analysis , Groundwater/chemistry , Water Pollutants, Chemical/analysis , Water Supply/analysis , Alkanesulfonic Acids/analysis , Caproates/analysis , Caprylates/analysis , Chromatography, High Pressure Liquid , Decanoic Acids/analysis , Environmental Monitoring/methods , Humans , New Jersey , Tandem Mass Spectrometry , Water
2.
Environ Sci Technol ; 43(12): 4547-54, 2009 Jun 15.
Article in English | MEDLINE | ID: mdl-19603675

ABSTRACT

After detection of perfluorooctanoic acid (PFOA) in two New Jersey (NJ) public water systems (PWS) at concentrations up to 0.19 microg/L, a study of PFOA in 23 other NJ PWS was conducted in 2006. PFOA was detected in 15 (65%) of the systems at concentrations ranging from 0.005 to 0.039 microg/L. To assess the significance of these data, the contribution of drinking water to human exposure to PFOA was evaluated, and a health-based drinking water concentration protective for lifetime exposure of 0.04 microg/L was developed through a risk assessment approach. Both the exposure assessment and the health-based drinking water concentrations are based on the previously reported 100:1 ratio between the concentration of PFOA in serum and drinking water in a community with highly contaminated drinking water. The applicability of this ratio to lower drinking water concentrations was confirmed using data on serum levels and water concentrations from other communities. The health-based concentration is based on toxicological end points identified by U.S. Environmental Protection Agency (USEPA) in its 2005 draft risk assessment Recent information on PFOA's toxicity not considered in the USEPA risk assessment urther supports the health-based concentration of 0.04 microg/L. In additional sampling of 18 PWS in 2007-2008, PFOA in most systems was below the health-based concentration. However, PFOA was detected above the health-based concentration in five systems, including one not previously sampled.


Subject(s)
Caprylates/chemistry , Fluorocarbons/chemistry , Water Pollutants, Chemical/chemistry , Water Supply/analysis , Water/chemistry , Environmental Monitoring , New Jersey , Ohio , West Virginia
3.
Sci Total Environ ; 377(2-3): 255-72, 2007 May 15.
Article in English | MEDLINE | ID: mdl-17363035

ABSTRACT

Samples of water and sediment from a conventional drinking-water-treatment (DWT) plant were analyzed for 113 organic compounds (OCs) that included pharmaceuticals, detergent degradates, flame retardants and plasticizers, polycyclic aromatic hydrocarbons (PAHs), fragrances and flavorants, pesticides and an insect repellent, and plant and animal steroids. 45 of these compounds were detected in samples of source water and 34 were detected in samples of settled sludge and (or) filter-backwash sediments. The average percent removal of these compounds was calculated from their average concentration in time-composited water samples collected after clarification, disinfection (chlorination), and granular-activated-carbon (GAC) filtration. In general, GAC filtration accounted for 53% of the removal of these compounds from the aqueous phase; disinfection accounted for 32%, and clarification accounted for 15%. The effectiveness of these treatments varied widely within and among classes of compounds; some hydrophobic compounds were strongly oxidized by free chlorine, and some hydrophilic compounds were partly removed through adsorption processes. The detection of 21 of the compounds in 1 or more samples of finished water, and of 3 to 13 compounds in every finished-water sample, indicates substantial but incomplete degradation or removal of OCs through the conventional DWT process used at this plant.


Subject(s)
Organic Chemicals/analysis , Pharmaceutical Preparations/analysis , Water Pollutants, Chemical/analysis , Water Supply/analysis , Detergents/analysis , Environmental Monitoring , Filtration , Flame Retardants/analysis , Flavoring Agents/analysis , Insect Repellents/analysis , Perfume/analysis , Pesticides/analysis , Plasticizers/analysis , Steroids/analysis , Water Purification/methods
4.
J Clin Laser Med Surg ; 19(1): 9-14, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11547819

ABSTRACT

BACKGROUND: Excimer laser angioplasty is a percutaneous treatment modality for management of selected patients with severe obstructive coronary artery disease. This technology entails application of multifiber catheters that vaporize intra-arterial plaque and thrombus with the 308-nm wavelength light. A coronary laser catheter ("OS") with increased space between its optic fibers (90 microns) at the tip was recently developed. The previous design used a closely packed fiber bundle ("CP") with a smaller space between the fibers (77 microns). We sought to determine the ablation characteristics of the new, OS design. METHODS: Experiments testing the new catheter and comparing it to the existing catheter included: (1) measurement of the laser output beam sizes and divergences; (2) evaluation of particulate matter generation during ablation of atherosclerotic tissue; (3) measurement of ablation hole sizes and tissue penetration rates; (4) histopathologic examination of laser-induced in vivo vessel wall injury. RESULTS: The new OS catheters produce a wider beam with higher divergence than the traditional CP catheters (6.7 degrees vs. 4.7 degrees, respectively). Testing two different levels of energy revealed the generation of a reduced number of particulate matter and shallower penetration depth with the OS catheter compared with traditional CP catheters. The OS catheters created a larger diameter of ablated hole than the CP catheters (for 2.0-mm catheters: 2.7 mm2 vs. 1.5 mm2, respectively, p = 0.01). Lasing with the OS catheters with slow advancement rates (0.2-0.5 mm/sec) resulted in creation of significantly larger-diameter holes than those produced at higher speeds (1-3 mm/sec). The in vivo vessel wall injury scores were similar among the two types of catheters tested. CONCLUSIONS: A new design of spaced optical fibers for coronary laser catheters provides increased tissue ablation in comparison to the traditional closely packed fibers catheter. Slow advancement rates during lasing with the new OS catheter are crucial for achievement of adequate plaque debulking.


Subject(s)
Angioplasty, Balloon, Laser-Assisted/instrumentation , Catheterization , Coronary Disease/surgery , Absorption , Equipment Design , Humans
5.
J Invasive Cardiol ; 12(11): 555-9, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11060568

ABSTRACT

PURPOSE: To determine the effects of the incidental exposure of stents to pulsed 308 nanometer ultraviolet excimer laser energy. METHODS: Five types of 316 L stainless-steel coronary stents were subjected to two types of study. First, for endurance testing, sixty stents were deployed in 3.0Eth 4.0 mm polymer tubes in three geometries. Up to 1,000 laser pulses were delivered while advancing a 2.0 mm eccentric catheter through the lumen of the stent. These stents were next subjected to 400 million simulated heartbeats and then analyzed for metal etching and fatigue. Second, six additional stents were irradiated with 1,000 pulses underwater and then analyzed for particulates, anions and cations liberated from the stent. RESULTS: Photomicroscopy revealed surface etching on a number of stents. Two stent models exhibited multiple strut fractures at the strut joints in both test samples and controls. In no case was a break observed at the site of laser-stent interaction. Breakage frequency was not significantly different between lazed stents and controls. Lazed stents produced a mean of 14 micrograms of sodium and 4 micrograms of iron more than controls. No excess particulates were detected. CONCLUSION: Under model conditions typical of clinical use, excimer laser treatment does not alter stainless-steel stent endurance or liberate clinically significant material from the stent.


Subject(s)
Atherectomy, Coronary/methods , Coronary Disease/surgery , Laser Therapy , Lasers , Stainless Steel , Stents , Humans
6.
Lasers Surg Med ; 22(1): 42-5, 1998.
Article in English | MEDLINE | ID: mdl-9443149

ABSTRACT

BACKGROUND AND OBJECTIVE: In a recent clinical trial, the 12-F laser sheath showed 95% success in completely explanting chronically implanted pacing leads smaller than 7.5-F diameter. For larger leads, two new sizes of laser sheath have been implemented, the 14-F and 16-F (outer diameter) devices, which accommodate leads up to 9.5- and 11.5-F, respectively. The object of this study was to determine the cutting ability of the larger devices compared to the 12-F design. MATERIALS AND METHODS: The rate of device advancement through fresh porcine aorta was measured for three sizes of laser sheath as pulsed ultraviolet light from a 308-nm XeCl excimer laser was applied. Dependent variables were fluence (mJ/mm2), laser pulse repetition rate, and pressure applied between the device and the tissue. RESULTS: At 60 mJ/mm2, 40 Hz repetition rate and 1.4 kg/cm2 pressure, all devices produced cutting rates in the range of 9-13 microns/pulse. Improvement in advancement per laser shot can be attained by increasing any independent variable studied. CONCLUSIONS: Physicians must apply only slightly greater force to the larger laser sheaths, and maximum available repetition rate and fluence implies maximum cutting speed.


Subject(s)
Electrodes, Implanted , Foreign Bodies/surgery , Laser Therapy/methods , Pacemaker, Artificial , Animals , Aorta/surgery , Equipment Design , Surface Properties , Swine
8.
New Dir Ment Health Serv ; (44): 113-22, 1989.
Article in English | MEDLINE | ID: mdl-2693934

ABSTRACT

Public psychiatry training in Oregon traces its roots to the community mental health movement of the 1960s and now includes a focus on training in the community and in state hospitals.


Subject(s)
Community Psychiatry/education , Education, Medical/history , Community Psychiatry/history , Education, Medical/trends , History, 20th Century , Internship and Residency , Oregon
9.
J Chromatogr ; 393(2): 237-53, 1987 Apr 29.
Article in English | MEDLINE | ID: mdl-3597602

ABSTRACT

Liquid-liquid extraction with dichloromethane is the Environmental Protection Agency's (EPA) method of choice for the analysis of acid or base neutral organic chemicals in water. Free radical chlorination and oxidation products of cyclohexene (the solvent preservative) in dichloromethane have been observed in extracts of chlorinated drinking water (after 10(5) fold concentration) by gas chromatography and gas chromatography-mass spectrometry. The chlorinated cyclohexene derivatives limit the quantitative and qualitative analysis of compounds eluting at Kovát's index less than 700-1000 and the use of these extracts for organoleptic and mutagenic studies. The effect of residual free chlorine in water on the cyclohexene present in the solvent was studied. Over ten cyclohexene derivatives were produced in every case when any residual free chlorine was present in the water. When chlorine is reduced to chloramine, the cyclohexene derivatives were greatly reduced in number and amount.


Subject(s)
Cyclohexanes/analysis , Hydrocarbons, Chlorinated/analysis , Methylene Chloride/analysis , Pharmaceutic Aids/analysis , Preservatives, Pharmaceutical/analysis , Water Supply/analysis , Chloramines/analysis , Chromatography, Gas , Cyclohexenes , Gas Chromatography-Mass Spectrometry , Methylene Chloride/isolation & purification , Solvents
11.
J Health Polit Policy Law ; 9(3): 389-410, 1984.
Article in English | MEDLINE | ID: mdl-6512220

ABSTRACT

In current discussions of "procompetitive" approaches to health policy, the enforcement of antitrust laws in health care markets is a strategy that has attracted increasing attention: the filing of consumer-oriented health suits provides a means to "redress" the typically imbalanced "political market" in health policy. This study examines an important aspect of the antitrust enforcement process, the decision by a state attorney general to undertake an aggressive antitrust enforcement program in the health area. Three variables were found to explain this decision: the political needs of a "politician-supplier," the organizational resources of a strategic institutional position, and the availability of a relatively favorable policy arena. An assessment of the future role of state attorneys general in this area suggests that their health antitrust initiatives will increase, but that various political and resource constraints are likely to inhibit their aggressiveness in pursuing these actions.


Subject(s)
Government , Health Policy/legislation & jurisprudence , Politics , State Government , Economic Competition , Ohio
12.
J Health Polit Policy Law ; 7(2): 460-87, 1982.
Article in English | MEDLINE | ID: mdl-7108175

ABSTRACT

Viewed from a historical (and a theoretical) perspective, current "pro-competition" policy proposals are unbalanced in their emphasis on promoting "free market" behavior by consumers rather than by suppliers in the health services market. A comprehensive competition policy would require removal of supply-side restraints on health providers. Based on evidence about the evolution of restraints on physicians, dentists, and optometrists in one state, this article speculates on the political feasibility of removing supply-side restraints and thereby implementing a true "competition policy". Historically, the political environment and the alignment of interest groups have favored the promulgation of stringent restraints on health services providers. While the political environment is more receptive to challenges to those restraints today, there is little evidence that such challenges will succeed at either the state or federal level.


Subject(s)
Economic Competition , Economics , Health Occupations/standards , Health Policy , Licensure , Advertising/legislation & jurisprudence , Ohio , Politics , Societies, Medical , United States
13.
J Health Polit Policy Law ; 7(3): 667-85, 1982.
Article in English | MEDLINE | ID: mdl-6765743

ABSTRACT

Historically, most health occupations have developed legal and ethical restrictions on price advertising and other characteristics of "commercial" practice. Many of these regulations recently have come under critical scrutiny, on the grounds that they inhibit free-market health care delivery, thus keeping prices high, and productivity and innovation low. To help inform current health policy deliberations, we analyze the political history of anticompetitive regulations in one health occupation, optometry. Restrictions on commercial practice arose as a result of professional optometry's purge of commercial elements in the 1930s. Optometry's success in achieving commercial-practice restrictions at the state level was determined by the economic structure of the ophthalmic goods and services industry in each state in the 1930s, and by the political resources and organization of the competing interest groups. Efforts to deregulate health occupations will precipate political conflict to the extent that economic interests are threatened. Opposition to deregulation will be based overtly on the grounds that quality of care will deteriorate, and a significant political investment by proponents of free-market health care will be required to overcome such opposition.


Subject(s)
Economic Competition , Economics , Health Policy , Marketing of Health Services/legislation & jurisprudence , Optometry/legislation & jurisprudence , Politics , Humans , United States
19.
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