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Absorption of copper(II) by creosote bush (Larrea tridentata): use of atomic and x-ray absorption spectroscopy.

Larrea tridentata (creosote bush), a common North American native desert shrub, exhibits the ability to take up copper(II) ions rapidly from solution. Following hydroponic studies, U.S. Environmental Protection Agency method 200.3 was used to digest the plant samples, and flame atomic absorption spectroscopy (FAAS) was used to determine the amount of copper taken up in different parts of the plant. The amount of copper(II) found within the roots, stems, and leaves was 13.8, 1.1, and 0.6 mg/g, respectively, after the creosote bush was exposed to a 63.5-ppm copper(II) solution for 48 h. When the plant was exposed to a 635-ppm copper(II) solution, the roots, stems, and leaves contained 35.0, 10.5, and 3.8 mg/g, respectively. In addition to FAAS analysis, x-ray microfluorescence (XRMF) analysis of the plant samples provided further confirmation of copper absorption by the various plant parts. X-ray absorption spectroscopy (XAS) elucidated the oxidation state of the copper absorbed by the plants. The copper(II) absorbed from solution remained as copper(II) bound to oxygen-containing ligands within the plant samples. The results of this study indicate that creosote bush may provide a useful and novel method of removing copper(II) from contaminated soils in an environmentally friendly manner.

Absorption↗

Maintenance of elevated lead levels in drinking water from occasional use and potential impact on blood leads in children.

The variation in lead concentration was measured by thermal ionisation mass spectrometry isotope dilution in household tap water throughout the day when the plumbing system was not fully flushed. After collection of an initial 125-ml water sample containing 119 micrograms/l and a 2-l sample, 125-ml samples were collected at hourly intervals for 8 h. The concentrations in the hourly samples remained in the range 35-52 micrograms/l compared with 1.7 micrograms/l for fully flushed water. High precision lead isotopic measurements showed that approximately 50% of the lead in these water samples derives from the tap 'housing' compared with the overall household system. A health risk assessment was performed employing the US Environmental Protection Agency Integrated Exposure Uptake Biokinetic Model. Predicted blood lead levels in infants only exceeded the 'levels of concern' of 10 micrograms/dl when 100% of the water consumed contained 100 micrograms Pb/1. It would appear that unless the infant consumed 100% of first flush water at lead concentrations of approximately 100 micrograms/l, the blood lead would not exceed the recommended 'level of concern'. However, if more than 0.51 was consumed in drinks and formulae using first flush water, then the blood lead could easily exceed the recommended level. Likewise, a pregnant mother could be at risk of consuming considerably more than the 0.51/day first flush water of the concentrations measured, or throughout the day, if the system were not fully flushed.

Adult↗

Reactivity-based VOC control for solvent products: more efficient ozone reduction strategies.

It has been almost 40 years since scientists and regulators began to publicly recognize that volatile organic compounds (VOCs) differ in their potential to form ozone. Since 1977, our understanding of the mechanisms by which VOCs contribute to ozone formation has grown substantially. An assessment of the science indicates that we now have sufficient understanding to develop and implement a more efficient approach to VOC control policy that will promote smarter, more cost-effective VOC controls. Furthermore, the U.S. Environmental Protection Agency's recently published Interim Guidance on Control of Volatile Organic Compounds in Ozone State Implementation Plans "encourages States to consider recent scientific information on the photochemical reactivity of volatile organic compounds (VOC) in the development of State implementation plans (SIPs)." As has been demonstrated by the California Air Resources Board's Aerosol Coatings Rule and the recent experience in Houston addressing high-reactivity VOCs, reactivity-based regulations may be more effective and efficient than mass-based rules in many applications. It is time for regulators, industry, and other stakeholders to work togetherto accelerate efforts to bring about a new paradigm in VOC control, in which the focus is on the ozone-forming potential of VOC emissions, rather than the mass of VOCs emitted.

Aerosols↗

Radon concentration in Jordanian drinking water and hot springs.

The radon concentration in Jordanian drinking water and hot springs has been measured using the electret-passive environmental radon monitoring method. This study maps out Jordanian water sources from the north to the south as well as the area around the capital Amman and the Jordan valley. Samples from 30 sources were collected and analysed during the period from November 2001 to June 2002. We have found that 60% of the drinking water sources have radon concentrations above the proposed US Environmental Protection Agency limit of 11 Bq l(-1); these are mostly situated in the northern region of the country. Fortunately, these sources supplied only a small number of people since they were mainly located in rural areas. Tap water in the capital Amman, where approximately 35% of the population live, has a very low radon concentration, 3.9 Bq l(-1). However, the isolated northern drinking water wells did show a radon level as high as 117 Bq l(-1). Hot springs in Jordan have a radon level ranging between 63 and 81 Bq l(-1), again mainly in the northern region. In general we conclude that Jordanian drinking water is safe as far as radon concentration is concerned with the exception of a few isolated local drinking water wells.

Environmental Monitoring↗

A study of urban housing demolitions as sources of lead in ambient dust: demolition practices and exterior dust fall.

Demolition of older housing for urban redevelopment purposes benefits communities by removing housing with lead paint and dust hazards and by creating spaces for lead paint-free housing and other community resources. This study was conducted to assess changes, if any, in ambient dust lead levels associated with demolition of blocks of older lead-containing row houses in Baltimore, Maryland (USA). In this article we present results based on dust-fall samples collected from fixed locations within 10 m of three demolition sites. In subsequent reports we will describe dust lead changes on streets, sidewalks, and residential floors within 100 m of the demolition sites. Geometric mean (GM) lead dust-fall rate increased by > 40-fold during demolition to 410 micro g Pb/m2/hr (2,700 micro g Pb/m2 per typical work day) and by > 6-fold during debris removal to 61 micro g Pb/m2/hr (440 micro g Pb/m2 per typical work day). Lead concentrations in dust fall also increased during demolition (GM, 2,600 mg/kg) and debris removal (GM, 1,500 mg/kg) compared with baseline (GM, 950 mg/kg). In the absence of dust-fall standards, the results were compared with the U.S. Environmental Protection Agency's (U.S. EPA's) dust-lead surface loading standard for interior residential floors (40 micro g/ft2, equivalent to 431 micro g/m2); daily lead dust fall during demolition exceeded the U.S. EPA floor standard by 6-fold on average and as much as 81-fold on an individual sample basis. Dust fall is of public health concern because it settles on surfaces and becomes a pathway of ambient lead exposure and a potential pathway of residential exposure via tracking and blowing of exterior dust. The findings highlight the need to minimize demolition lead deposition and to educate urban planners, contractors, health agencies, and the public about lead and other community concerns so that society can maximize the benefits of future demolition activities nationwide.

Baltimore↗

Ontario Medical Association position paper on health effects of ground-level ozone, acid aerosols and particulate matter.

This review of the evidence of the health effects of air pollutants focuses on research conducted in Ontario. Seven key Ontario studies are cited. These findings are highly significant for people living in the Great Lakes basin (and particularly the Windsor-Quebec corridor), where high levels of certain air pollutants (eg, ground-level ozone and ultra-fine particles) occur more frequently than in other parts of Canada. The issue is a serious one, requiring an integrated and comprehensive approach by many stakeholders, including the active involvement of organized medicine. It is important that the health effects of these air pollutants are understood. Governments must act to reduce emission levels through statue and regulation bolstered by noncompliance penalties. The findings of research have included the following: in a Toronto study, a 2% to 4% excess of respiratory deaths were attributable to pollutant levels; children living in rural Ontario communities with the highest levels of airborne acids were significantly more likely to report at least one episode of bronchitis, as well as to show decreases in lung function; and have been linked to increases in pollutants, emergency room visits and hospitalizations in Ontario. Every Ontarian is affected by air pollutants, although he or she may be unaware of the asymptomatic effects such as lung and bronchial inflammation. This health problem is preventable; while physicians know of the adverse health impacts of air pollution and they are concerned, individually they now focus on the treatment of symptoms. The major recommendations of the report are as follows: Enactment of more stringent sulphur and nitrogen oxide emission limits, including a provincewide sulphur dioxide reduction of 75% from current cap levels, and the maximum allowable nitrogen oxides emission limits of 6000 tonnes annually from Ontario Hydro. New transportation sector emission limits that should include California-level standards for light and heavy duty vehicles, reductions from off-road engines, an expanded vehicle inspection and maintenance program, and tougher standards for sulphur-in-fuel content. Petitioning the United States Environmental Protection Agency administrator under Section 115 of the United States Clear Air Act to require reductions in the American emission of sulphur dioxide and nitrogen oxides, which damage the health of Canadian residents and their environment. Physician advice to patients about the risks of smog exposure, physician support for more health effects research on air pollution, and physician promotion of the development of air pollution-related health education materials. The recommendations discussed in this paper will, if acted upon, lead to a significant reduction in the overall burden of illness from air pollutants, especially in children and the elderly. These recommendations have been selected from a review of recommendations made by various authorities, and are those that the OMA feels a particular responsibility to support.

Aerosols↗

Analysis of a cluster of cases of Wegener granulomatosis.

BACKGROUND: Wegener granulomatosis is a chronic inflammatory autoimmune disease of unknown etiology. The sporadic occurrence, lack of familial or genetic associations, and rising incidence suggest possible exposure to environmental agents as causative for this disease. OBJECTIVE: The objective of this study was to examine possible environmental triggers of Wegener granulomatosis. METHODS: While conducting an environmental survey of potential precipitants of Wegener granulomatosis on a cohort of patients seen at Doylestown Hospital and at the University of Pennsylvania, we identified a cluster of cases in the Dublin, Pennsylvania, region. Through hospital records and patient contacts, we located 7 cases diagnosed in a 3-year period within a 10-mile radius of an Environmental Protection Agency (EPA) Superfund toxic waste site. The radius of inclusion represents a population of approximately 50,000 individuals. Assuming complete ascertainment of cases--which is unlikely given the methods used to acquire patients--the prevalence is 2- to 4-fold greater than the expected rate of 3 per 100,000. We identified toxins at or above "action level" within the demarcated geographic region using published data from the EPA. Furthermore, we queried patients regarding their particular chemical exposures. RESULTS: These patients with Wegener granulomatosis were possibly exposed to high levels of trichloroethylene (TCE), vinyl chloride, methyl tertiary-butyl ether (MTBE), dichloroethene (DCE), and chromic acid from several industrial waste sites within the area. Additionally, these patients reported a total of greater than 30 possible exposures, including the aforesaid chemical contaminants. Three of 5 patients whose water source is known had well water that exposed them to industrial runoff and necessitated EPA intervention. CONCLUSION: This data, along with other epidemiologic studies, suggest possible toxic exposures as potentially correctable risk factors for Wegener granulomatosis. We encourage clinicians to seek data that suggests an unusual environmental exposure and to solicit information that might implicate an industrial source for these exposures.

Carcinogens, Environmental↗

Validation and calibration of a model used to reconstruct historical exposure to polycyclic aromatic hydrocarbons for use in epidemiologic studies.

OBJECTIVES: We previously developed a historical reconstruction model to estimate exposure to airborne polycyclic aromatic hydrocarbons (PAHs) from traffic back to 1960 for use in case-control studies of breast cancer risk. Here we report the results of four exercises to validate and calibrate the model. METHODS: Model predictions of benzo[a]pyrene (BaP) concentration in soil and carpet dust were tested against measurements collected at subjects' homes at interview. In addition, predictions of air intake of BaP were compared with blood PAH-DNA adducts. These same soil, carpet, and blood measurements were used for model optimization. In a separate test of the meteorological dispersion part of the model, predictions of hourly concentrations of carbon monoxide from traffic were compared with data collected at a U.S. Environmental Protection Agency monitoring station. RESULTS: The data for soil, PAH-DNA adducts, and carbon monoxide concentrations were all consistent with model predictions. The carpet dust data were inconsistent, suggesting possible spatial confounding with PAH-containing contamination tracked in from outdoors or unmodeled cooking sources. BaP was found proportional to other PAHs in our soil and dust data, making it reasonable to use BaP historical data as a surrogate for other PAHs. Road intersections contributed 40-80% of both total emissions and average exposures, suggesting that the repertoire of simple markers of exposure, such as traffic counts and/or distance to nearest road, needs to be expanded to include distance to nearest intersection.

Calibration↗

Determination of polycyclic aromatic hydrocarbons in dungeness crabs (Cancer magister) near an aluminum smelter in Kitimat Arm, British Columbia, Canada.

An aluminum smelter situated at the head of Kitimat Arm (BC, Canada) has discharged polycyclic aromatic hydrocarbons (PAHs) into the receiving waters since 1954. The purpose of the present study was to examine the distribution of PAHs contaminants in dungeness crabs (Cancer magister) collected in Kitimat Arm and Douglas Channel (BC, Canada) by determining the concentrations of PAHs in the hepatopancreas and muscle tissues of crabs by using gas chromatography-mass spectrometry. Crabs were collected at specific sites down the Arm from the smelter on four separate occasions over a three-year period. Hepatopancreas and muscle tissues of the crabs were analyzed for 10 of the 16 PAH priority pollutants recommended by the U.S. Environmental Protection Agency. Results of the studies showed that the crabs had detectable levels of PAHs in hepatopancreas and muscle tissues. The highest concentrations of PAHs in the tissues were found at a site near the aluminum smelter, the alleged point source of PAH discharge. The concentrations of PAH analytes were high in crabs collected close to the smelter and at lower levels in crabs collected throughout Douglas Channel. These results show that PAHs discharged by the smelter were bioavailable to the crabs. The concentration of each PAH analyte in the hepatopancreas was found to be strongly related to its water solubility. However, the PAH analyte concentrations in the hepatopancreas and muscle did not appear to correlate highly with each other.

Animals↗

Sampling design, response rates, and analysis weights for the National Human Exposure Assessment Survey (NHEXAS) in EPA region 5.

For the Phase I field test of the National Human Exposure Assessment Survey (NHEXAS) in U.S. Environmental Protection Agency (EPA) Region 5, this paper presents the survey sampling design, the response rates achieved, and the sample weighting procedure implemented to compensate for unit nonresponse. To enable statistically defensible inferences to the entire region, a sample of about 250 members of the household population in EPA Region 5 was selected using a stratified multistage probability-based survey sampling design. Sample selection proceeded in four nested stages: (1) sample counties; (2) area segments based on Census blocks within sample counties; (3) housing units (HUs) within sample segments; and (4) individual participants within sample households. Each fourth-stage sample member was asked to participate in 6 days of exposure monitoring. A subsample of participants was asked to participate in two rounds of longitudinal follow-up data collection. Approximately 70% of all sample households participated in household screening interviews in which rosters of household members were developed. Over 70% of the sample subjects selected from these households completed the Baseline Questionnaire regarding their demographic characteristics and potential for exposures. And, over 75% of these sample members went on to complete at least the core environmental monitoring, including personal exposures to volatile organic compounds (VOCs) and tap water concentrations of metals. The sample weighting procedures used the data collected in the screening interviews for all household members to fit logistic models for nonresponse in the later phases of the study. Moreover, the statistical analysis weights were poststratified to 1994 State population projections obtained from the Bureau of the Census to ensure consistency with other statistics for the Region.

Adolescent↗

Characterization of spirometric function in residents of three comparison communities and of three communities located near waste incinerators in North Carolina.

Waste incinerators are an increasingly common means of solid waste disposal. However, little is documented about the physical health of community members who live close to incinerators. During a 3-yr epidemiological study, spirometric lung function was tested once annually among residents from 3 communities surrounding a hazardous waste, biomedical, or municipal incinerator and among residents in 3 comparison communities. A total of 1,016 nonsmoking individuals, aged 8-80 yr, participated during at least 1 of the 3 yr of the study; 358 individuals participated all 3 yr. Daily air-quality sampling was done for 1 mo/yr in all 6 communities. The average monthly concentrations of particulate matter with diameters of 2.5 microns and less (PM2.5 [range = 14.6-31.5 micrograms/m3]) in all communities were similar during the 3 yr of study. The mean daily PM2.5 concentrations were significantly less than the U.S. Environmental Protection Agency's allowable 24-hr standard of 65 micrograms/m3. Individual incinerators contributed less than 2.5% of the areas' total PM2.5 levels. There was no difference in percent predicted forced vital capacity, forced expiratory volume in 1 sec, or forced expiratory flow rate over the middle 50% of the forced vital capacity among members of the incinerator communities, compared with nonincinerator communities, and there were no significant differences in lung function within the 3 sets of communities. There was no evidence from this study that an association existed between residence in these 3 waste incinerator areas, which met state and federal emissions regulations, and average spirometric pulmonary function of nonsmoking community members.

Adolescent↗

Associations between air pollution and mortality in Phoenix, 1995-1997.

We evaluated the association between mortality outcomes in elderly individuals and particulate matter (PM) of varying aerodynamic diameters (in micrometers) [PM(10), PM(2.5), and PM(CF )(PM(10) minus PM(2.5))], and selected particulate and gaseous phase pollutants in Phoenix, Arizona, using 3 years of daily data (1995-1997). Although source apportionment and epidemiologic methods have been previously combined to investigate the effects of air pollution on mortality, this is the first study to use detailed PM composition data in a time-series analysis of mortality. Phoenix is in the arid Southwest and has approximately 1 million residents (9. 7% of the residents are > 65 years of age). PM data were obtained from the U.S. Environmental Protection Agency (EPA) National Exposure Research Laboratory Platform in central Phoenix. We obtained gaseous pollutant data, specifically carbon monoxide, nitrogen dioxide, ozone, and sulfur dioxide data, from the EPA Aerometric Information Retrieval System Database. We used Poisson regression analysis to evaluate the associations between air pollution and nonaccidental mortality and cardiovascular mortality. Total mortality was significantly associated with CO and NO(2) (p < 0.05) and weakly associated with SO(2), PM(10), and PM(CF) (p < 0. 10). Cardiovascular mortality was significantly associated with CO, NO(2), SO(2), PM(2.5), PM(10), PM(CF) (p < 0.05), and elemental carbon. Factor analysis revealed that both combustion-related pollutants and secondary aerosols (sulfates) were associated with cardiovascular mortality.

Aged↗

Evaluating ecological indicators: lakes in the northeastern United States.

We use data from a survey of several hundred lakes in the northeastern United States by the U.S. Environmental Protection Agency to illustrate an approach to identifying promising indicators of lake condition. We construct a hypothetical gold standard of water quality from the first principal component of 16 chemical variables measured in the lakes, and examine its associations with 71 candidate indicators based on measurements of human activity, birds, fish and zooplankton in the lakes or their watersheds. Nonparametric summaries of these associations--based on rank correlations and receiver-operating-characteristic curves--suggest that variables summarizing the extent of human disturbance are generally the strongest indicators. To the extent that our water-quality variable is a useful proxy for ecological condition, our results suggest that easily-obtained measures of human activity are at least as predictive as many of the harder-to-measure biological indicators that have been proposed.

Animals↗

A bayesian approach to parameter estimation for a crayfish (Procambarus spp.) bioaccumulation model.

Bioaccumulation models are used to describe chemical uptake and clearances by organisms. Averaged input parameter values are traditionally used and yield point estimates of model outputs. Hence, the uncertainty and variability of model predictions are ignored. Probabilistic modeling approaches, such as Monte Carlo simulation and the Bayesian method, have been recommended by the U.S. Environmental Protection Agency to provide a quantitative description of the degree of uncertainty and/or variability in risk estimates in ecological hazards and human health effects. In this study, a Bayesian analysis was conducted to account for the combined uncertainty and variability of model parameters in a crayfish bioaccumulation model. After a 5-d exposure in the LaBranche Wetlands (LA, USA), crayfish were analyzed for polycyclic aromatic hydrocarbon concentrations and lipid fractions. The posterior distribution of model parameters were derived from the joint posterior parameter distributions using a Markov chain Monte Carlo approach and the experimental data. The results were then used to predict the distribution of chrysene concentration versus time in the crayfish to compare the predicted ranges at the different study sites.

Animals↗

The relationship between lead and crime.

This study investigates the association between air-lead levels and crime rates across 2,772 U.S. counties. Data for the analysis come from the Environmental Protection Agency, the Bureau of Census, and the Federal Bureau of Investigation. Results suggest that air-lead levels have a direct effect on property and violent crime rates even after adjusting for general levels of air pollution and several structural covariates of crime. We also find that resource deprivation interacts with air-lead levels. The association between air-lead levels and crime rates-property and violent-is strongest in counties that have high levels of resource deprivation and weakest in counties that have low levels of deprivation. This interaction is consistent with arguments and evidence in the health care literature that populations most at risk of lead poisoning are least likely to get the resources required to prevent, screen, and treat the illness.

Air Pollutants↗

Breath measurements as volatile organic compound biomarkers.

A brief review of the uses of breath analysis in studies of environmental exposure to volatile organic compounds (VOCs) is provided. The U.S. Environmental Protection Agency's large-scale Total Exposure Assessment Methodology Studies have measured concentrations of 32 target VOCs in the exhaled breath of about 800 residents of various U.S. cities. Since the previous 12-hr integrated personal air exposures to the same chemicals were also measured, the relation between exposure and body burden is illuminated. Another major use of the breath measurements has been to detect unmeasured pathways of exposure; the major impact of active smoking on exposure to benzene and styrene was detected in this way. Following the earlier field studies, a series of chamber studies have provided estimates of several important physiological parameters. Among these are the fraction, f, of the inhaled chemical that is exhaled under steady-state conditions and the residence times. tau i in several body compartments, which may be associated with the blood (or liver), organs, muscle, and fat. Most of the targeted VOCs appear to have similar residence times of a few minutes, 30 min, several hours, and several days in the respective tissue groups. Knowledge of these parameters can be helpful in estimating body burden from exposure or vice versa and in planning environmental studies, particularly in setting times to monitor breath in studies of the variation with time of body burden. Improvements in breath methods have made it possible to study short-term peak exposure situations such as filling a gas tank or taking a shower in contaminated water.

Biomarkers↗

[Control of lead emissions from a battery repair shop in the city of Rio de Janeiro using the air as indicator].

Lead levels in the air surrounding a battery repair shop (BRS) located in the Olaria neighborhood (Rio de Janeiro, Brazil) were monitored from April to July 1999. Most of the samples collected within 25 meters of the BRS exceeded the limit of 1.5 micro g.Pb.m-3 established by the United States Environmental Protection Agency (EPA). These results were published in a previous article (Quiterio et al., 2001). In the current study, installation of a Venture ventilation system and some changes in the operational procedure were proposed. After the modifications in the BRS, a new monitoring campaign was performed (August and September, 2000). Three points were selected for air collection, corresponding to the most critical points found in the previous assessments. The new concentrations ranged from 0.8 to 17.6 micro g.Pb.m-3, showing that lead emissions into the environment had decreased adequately. However, concentration at the chimney exhaust was still higher than EPA limits, and further improvements in the installations and procedures are definitely needed.

Air Pollutants↗

Assessment of toxicity of heavy metal contaminated soils by the toxicity characteristic leaching procedure.

The concentrations of Cu, Zn, Pb and Cd in soils near a lead-zinc mine located in Shangyu, Zhejiang Province, China, were determined and their toxicity was assessed using the toxicity characteristic leaching procedure (TCLP) developed by the United States Environmental Protection Agency. The TCLP method is a currently recognized international method for evaluation of heavy metal pollution in soils. The available levels of Cu, Zn, Pb and Cd were 8.2-36, 23-143, 6.4-1367 and 0.41-2.2 mg kg(-1), respectively, while the international standards were 15, 25, 5 and 0.5 mg kg(-1), respectively. Soils around the mine were more polluted with Zn and Pb, followed by Cd and Cu. Moreover, the levels of heavy metals in the soils extracted by TCLP indicated that extraction fluid 2 was more effective than extraction fluid 1 in extracting the heavy metals from the polluted soils and there was a positive correlation between fluids 1 and 2. Available heavy metal contents determined by TCLP were correlated with soil total heavy metal contents.

Cadmium↗