Urine analysis for the evaluation of environmental exposures to aromatic hydrocarbons

The authors have developed a dynamic headspace (purge-and-trap) gas chromatographic method, with photoionization detection, for the determination of benzene (C6H6), toluene (C7H8), ethylbenzene (C8H10), and isomeric (o-, m-, p-) xylenes (C8H10) (BTEX) in urine. Detection limits ranged between 15 and 35 ng/l, relative standard deviations between 0.2 and 10%, and accuracy between 80 and 100%. The primary objective of this study was to use this new method to establish baseline concentration data for BTEX in the urine of the general population of Zagreb, Croatia. A second objective was to evaluate the effect of cigarette smoking on those baseline values. BTEX were analyzed in the urine of 72 subjects (36 nonsmokers and 36 smokers) without occupational exposure to BTEX. The nonsmokers had measurable BTEX in their urine, except for ethylbenzene in 13 and o-xylene in 15 of the samples. Values for BTEX were markedly higher among smokers than nonsmokers. Because the sources of BTEX exposure are commonly derived (i.e., vehicle exhausts and smoking), their values in subjects' urine were significantly intercorrelated. Levels of toluene and o-xylene were correlated significantly with the number of cigarettes smoked per day. The use of purge-and-trap gas chromatography with photoionization detection to determine BTEX in urine offers a convenient approach for biological monitoring of the general population. Study data provide referent values for BTEX in urine, which can be used as biomarkers for environmental exposures. Smoking contributes significantly to the urinary concentration of BTEX.     

某区低浓度苯系物作业场所与工人职业健康监护现状调查

目的探讨区域内企业工人低浓度苯系物防护状况、接触水平、管理现状及其对工人健康影响的特点,为企业制定健康监护策略和采取有效措施保护工人身体健康提供依据。方法对企业工作场所现状进行调查,并对空气中苯、甲苯、二甲苯浓度进行监测,对低浓度苯系物接触工人进行职业健康监护,将相应企业不接触苯的工人作为内对照,对健康监护资料进行统计分析。结果该企业职业健康监护977人,查出各类实验室检查结果异常者244人(361项次),异常率为24.97%;低浓度苯系物接触工人的白细胞计数下降人数与对照组比较差异有统计学意义(χ2=39.89,P0.01)。结论在现有的防护状况和管理措施下,从事低浓度苯系物作业的工人出现比较明显的外周白细胞计数改变,需要进一步依法加强对低浓度苯系物作业工人的健康监护并改善劳动环境。     

BTEX air concentrations and self-reported common health problems in gasoline sellers from Cotonou,Benin

To examine the relation between BTEX exposure levels and common self-reported health problems in 140 gasoline sellers in Cotonou, Benin, a questionnaire documenting their socioeconomic status and their health problems was used, whereas 18 of them went through semi-directed qualitative individual interviews and 17 had air samples taken on their workplace for BTEX analysis. Median concentrations for BTEX were significantly lower on official (range of medians: 54–207?μg/m³, n?=?9) vs unofficial (148–1449?μg/m³, n?=?8) gasoline-selling sites (p?vs official selling sites (p?相似文献   

Biological monitoring of nickel

Measurements of nickel in body fluids, excreta, and tissues from humans with occupational, environmental, and iatrogenic exposures to nickel compounds are comprehensively reviewed. Correlations between levels of human exposures to various classes of nickel compounds via inhalation, oral, or parenteral routes and the corresponding concentrations of nickel in biological samples are critically evaluated. The major conclusions include the following points: Measurements of nickel concentrations in body fluids, especially urine and serum, provide meaningful insights into the extent of nickel exposures, provided these data are interpreted with knowledge of the exposure routes, sources, and durations, the chemical identities and physical-chemical properties of the nickel compounds, and relevant clinical and physiological information, such as renal function. Nickel concentrations in body fluids should not, at present, be viewed as indicators of specific health risks, except in persons exposed to nickel carbonyl, for whom urine nickel concentrations provide prognostic guidance on the severity of the poisoning. In persons exposed to soluble nickel compounds (e.g., NiCl2, NiSO4), nickel concentrations in body fluids are generally proportional to exposure levels; absence of increased values usually indicates non-significant exposure; presence of increased values should be a signal to reduce the exposure. In persons exposed to less soluble nickel compounds (e.g., Ni3S2,NiO), increased concentrations of nickel in body fluids are indicative of significant nickel absorption and should be a signal to reduce the exposures to the lowest levels attainable with available technology; absence of increased values does not necessarily indicate freedom from the health risks (e.g., cancers of lung and nasal cavities) associated with exposures to certain relatively insoluble nickel compounds.     

Urinary excretion of 3-phenoxybenzoic acid in middle-aged and elderly general population of Japan

Limited data are available on the background levels of exposure to synthetic pyrethroid (PYR) in Japan, despite their frequent application for agriculture and indoor extermination and possible effects of chronic and/or low-dose PYR exposure on human health. This study was conducted to describe the level and distribution of one of the major PYR metabolites, 3-phenoxybenzoic acid (3-PBA), in urine samples collected from a general population in Japan. The subjects were 535 individuals (184 men and 351 women; 61.5±9.8 years of age, mean±S.D.) residing in a town in Hokkaido, a dairy and agricultural area. Urinary 3-PBA was found detectable in 98% of samples above the limit of detection of 0.02 μg/l. The geometric mean values of urinary 3-PBA in occupationally exposed farmers (n=87) and the remaining general group without occupational exposure (n=448) were 0.38 and 0.29 μg/l, respectively, ranging from <LOD to 17.09 μg/l. No significant differences in urinary 3-PBA concentrations were shown between these two groups. Moreover, 3-PBA concentrations were found comparable to those reported in some countries. The present study is, to our knowledge, the first report of a biological monitoring study of urinary 3-PBA, which elucidated the background environmental exposure level of PYR in the Japanese general population without occupational exposure. Further nationwide studies covering different seasons and age distribution are needed to monitor the urinary 3-PBA levels in Japan.     

Relationships between levels of volatile organic compounds in air and blood from the general population

The relationships between levels of volatile organic compounds (VOCs) in blood and air have not been well characterized in the general population where exposure concentrations are generally at parts per billion levels. This study investigates relationships between the levels of nine VOCs, namely, benzene, chloroform, 1,4-dichlorobenzene, ethylbenzene, methyl tert-butyl ether (MTBE), tetrachloroethene, toluene, and m-/p- and o-xylene, in blood and air from a stratified random sample of the general US population. We used data collected from 354 participants, including 89 smokers and 265 nonsmokers, aged 20-59 years, who provided samples of blood and air in the National Health and Nutrition Examination Survey (NHANES) 1999-2000. Demographic and physiological characteristics were obtained from self-reported information; smoking status was determined from levels of serum cotinine. Multiple linear regression models were used to investigate the relationships between VOC levels in air and blood, while adjusting for effects of smoking and demographic factors. Although levels of VOCs in blood were positively correlated with the corresponding air levels, the strength of association (R(2)) varied from 0.02 (ethylbenzene) to 0.68 (1,4-DCB). Also the blood-air relationships of benzene, toluene, ethylbenzene, and the xylenes (BTEX) were influenced by smoking, exposure-smoking interactions, and by gender, age, and BMI, whereas those of the other VOCs were not. Interestingly, the particular exposure-smoking interaction for benzene was different from those for toluene, ethylbenzene, and the xylenes. Whereas smokers retained more benzene in their blood at increasing exposure levels, they retained less toluene, ethylbenzene, and xylenes at increasing exposure levels. Investigators should consider interaction effects of exposure levels and smoking when exploring the blood-air relationships of the BTEX compounds in the general population.     

Biomonitoring of human exposure to triazine herbicides

Triazine herbicides are very common and only 0.1 % reach the target pests, while the rest moves into other environmental compartments. Their fate in the environment depends on their movement through the air, water, and soil and on the rate of their degradation or transformation. Triazine compounds may be transformed by water, microorganisms, and sunlight. Widespread use and persistence of triazine herbicides in soil has resulted in contamination of surface, drinking, and even rain water with parent compounds and degradation products, posing a risk to the general population.The metabolism and effects of triazine herbicides have been studied in experimental animals and in experiments in vitro. There are only a few studies of their metabolism and excretion in humans. Agricultural and manufacturing workers are exposed to triazines during application and production. Human exposure is monitored by determining parent compounds and their metabolites in urine. Due to the low concentrations of urinary metabolites in occupationally exposed persons, very sensitive analytical methods are required. This paper describes the structure and properties of symmetric triazine herbicides, their metabolism, and effects in humans and animals and the levels of these compounds in the urine of occupationally exposed persons.     

Dioxins and furans: origins and risks

A bibliographic review is presented with the objective of describing the origin and the risks to the public health of dioxins and furans and getting familiar with some research areas about these compounds. The review has considered 16 selected references covering a period of approximately twelve years (1986 to 1997). The main conclusions were: a) These compounds are from nonnatural origin, considered highly toxic, extremely persistent in the environment, and they have been detected in all environmental matrices like: soil, sediments, air, water, animals and plants; b) emissions of these compounds to the atmosphere come primarily from combustion processes; c) atmospheric dispersion, deposition and subsequent accumulation in the food chain seem to be the major exposure pathway to the general population; d) due to their lipophilic characteristic and persistence in the environment, these compounds accumulate in adipose tissues, being food of animal origin those which present higher concentrations; e) in Brazil, the few studies conducted, with the measurement of concentrations of these compounds in the environment have showed levels comparable to those obtained in Germany. The authors recommend the development of further studies about these compounds in Brazil, specially about their accumulation in food and in human tissue     

基于生物监测的儿童尿中对硝基苯酚暴露评估

目的 基于尿中对硝基酚 (para-nitrophenol,PNP)的生物监测评估儿童体内暴露负荷,为保护儿童健康提供科学依据。方法 选取江苏省某县参加“宫内环境化学物暴露对婴幼儿生长发育影响”队列的母亲于2009 年6 月-2010 年1月期间所产441名3岁幼儿作为研究对象,在其父母协助下完成问卷调查和尿样采集,采用气相色谱-串联质谱法(GC-MS/MS)检测儿童尿中PNP的含量,通过非参数检验和多元线性回归分析可能的影响因素,基于尿样监测数据评估并比较了儿童体内PNP负荷水平。结果 所有研究对象尿中均可检出对PNP,肌酐校正与未校正的PNP几何均值分别为12.14 μg/g cre.和5.08 μg/L。男童与女童PNP暴露水平未见统计学差异;多元线性回归结果显示,采样季节是影响PNP暴露水平的重要因素,夏季暴露水平高于其他季节,差异具有统计学意义(P<0.05),儿童尿中PNP浓度高于国外同类研究。结论 研究地区儿童普遍高暴露于PNP或其前体物质,其对儿童的潜在健康风险不容忽视。     

Concentrations of persistent toxic compounds in the Spanish population: a puzzle without pieces and the protection of public health

The contamination by persistent toxic compounds (PTCs) of the general population is a fact of relevance from a public health perspective. It is also relevant to health care professionals, as well as for environmental, food, industrial and economic policies.Though in Spain information on food contamination by PTCs shows large time and geographic gaps, the scarcity of data is even more severe on the concentrations that PTCs have in people: a representative study of a general healthy population living in a wide geographic area has never been conducted in the country. However, the available studies indicate that around 80-100% of the population has detectable concentrations of DDE, PCBs, hexachlorbenzene or lindane. Studies on the effects that PTCs have upon humans are extremely infrequent in Spain. Yet, the international literature suggests that some PTCs may induce significant biological and clinical effects at doses below those traditionally deemed "safe". The mechanism of action of PTCs are not restricted to endocrine disruption. Assessing the clinical and social relevance of the more subtle and long-term effects of PTCs presents interesting challenges and opportunities.Spain and other European countries lack population indicators on the impact that environmental processes have on human health. Several government levels have a role to fulfill in the monitoring of biological levels of PTCs among persons in order to assess the risks of adverse health effects.Along with over a hundred other countries. Spain will soon try to implement the Stockholm treaty on persistent organic pollutants (POPs). This constitutes a new opportunity to develop more efficient policies to control PTC residues in food, humans and the environment. As part of the treaty implementation it is necessary to launch a Report on factors that influence body concentrations of PTCs in the Spain general population.     

Toxicology of 85Kr: chronic exposure studies

Male and female Wistar rats were exposed chronically to graded doses of 85Kr to determine long-term biological effects of simulated environmental exposure. Rats were exposed in 4 groups, including room air-exposed controls and 3 groups exposed to 85Kr concentrations equivalent to 10(2), 10(3) and 10(4) times the maximum permissible concentration (MPC) for the general population (3 X 10(-7) microCi/ml). Exposures continued 24 hr/day, 7 days/week for 808 days, until only approximately 10% of the original 400 rats were alive. No effect of 85Kr exposure was observed on weight gain or tumor incidence, including leukemias. The results support the adequacy of established 85Kr exposure limits for the general population in light of the absence of evidence of build-up in tissues after chronic exposure and the lack of exposure-related biological effects in rats after near-lifespan exposure to concentrations equivalent to 10,000 times the MPC.     

The U.S. National Health and Nutrition Examination Survey and human exposure to environmental chemicals

Researchers are increasingly interested in using human biomonitoring - the measurement of chemicals, their metabolites or specific reaction products in biological specimens/body fluids - for investigating exposure to environmental chemicals. General population human biomonitoring programs are useful for investigating human exposure to environmental chemicals and an important tool for integrating environment and health. One of these programs, the National Health and Nutrition Examination Survey (NHANES), conducted in the United States is designed to collect data on the health and nutritional status of the noninstitutionalized, civilian U.S. population. NHANES includes a physical examination, collecting a detailed medical history, and collecting biological specimens (i.e., blood and urine). These biological specimens can be used to assess exposure to environmental chemicals. NHANES human biomonitoring data can be used to establish reference ranges for selected chemicals, provide exposure data for risk assessment, and monitor exposure trends.     

Levels of persistent toxic substances in the general population in Italy

Human exposure to persistent toxic substances (PTS) occurs daily, mainly through diet. As a consequence of continuous exposure, and because of their biological persistence, PTS are virtually present in all individuals, stored in their fatty tissues. The exposure of the Italian general population to PTS is a fact of relevance from a public health perspective, because of the number of toxic effects associated to these compounds, possibly occurring even at the current background level of exposure. In spite of this, data on PTS concentrations in humans, considered the best dose metric to carry out an adequate risk assessment, are scarce, as shown by the overview of available information we hereafter present. The Convention of Stockholm on persistent organic pollutants (POP), a group of highly toxic PTS, has entered into force last May. This will oblige parties to develop national implementation plans, thus creating a new opportunity to develop more efficient policies to control POP and other PTS present in food, humans and the environment.     

Organizational components and structural features of EPA's new Human Exposure Research Program.

Modern technology has brought about a dramatic increase in the production and consumption of man-made chemicals and in their resulting emissions. It is clear that these emissions and their by-products will likely affect our environment and have a health impact on the population exposed to them. Knowledge of exposure is required to document the impact of these emissions on human health. However, measuring, interpreting, and characterizing human exposures are extraordinarily complex processes because exposures may occur by multiple routes, multiple sources, and they are subject to a wide range of temporal, spatial, and source variations often from both anthropogenic and non-anthropogenic sources. The Environmental Protection Agency's approach to exposure research has often been insufficient to understand and mitigate these complex real-word exposures. For example, we do not know the population exposure distributions of most pollutants and the relative contributions of sources to these distributions. Without this knowledge as input into EPA's risk management process, EPA's may not be making the most effective environmental management decisions for reducing human health risks. The Human Exposure Research Program is a direct response to this need to understand how and to what extent humans are exposed to environmental pollutants.     

Exposure and allergy to dust mites in general and working environment in Croatia

This paper gives a review of the most important impacts of exposure to dust mites in general and working environment on human health. The Institute for Medical Research and Occupational Health in Zagreb, Croatia, has been investigating the frequency and exposure levels of allergies to pyroglyphid and non-pyroglyphid mites in Croatia for the last 10 years. Investigations were performed in general urban and rural population from the inland and coastal Croatia, and several industrial inland populations occupationally exposed to organic dusts. Mite species and levels of pyroglyphid mites allergens (Der p 1, Der f 1) were established in house dust samples taken from the floors of bedrooms and living rooms and in several industrial dust samples. The frequency of allergies to pyroglyphid mites in general urban population of inland Croatia is about 20%, with significant general indoor exposure to these mites (median value for Der p 1: 0.85 microg/g of dust). General adult population of the coastal region had a significantly higher exposure to pyroglyphid mites (median value for Der p 1: 4.5 microg/g of dust), yet showed a significantly lower frequency of allergies to these mites (about 5%). New studies are necessary to investigate possible genetic and environmental factors involved in the mechanisms which protect coastal population from the development of mite allergy. Acarological and statistical analyses have shown that the high frequency of sensitisation to non-pyroglyphid mites found in the general and working populations of the inland region is not related to environmental exposure to these mites, but to the cross-reactivity between pyroglyphid and non-pyroglyphid mites and to false positive skin reactions in prick testing, particularly to T. putrescentiae. So far, results do not indicate that pyroglyphid mites are occupational allergens in paper-recycling, fish-processing and tobacco-processing.     

Benzene,toluene, ethylbenzene and xylene concentrations in atmospheric ambient air of gasoline and CNG refueling stations

This study aimed to assess workers’ exposure to benzene, toluene, ethylbenzene, and xylene (BTEX) compounds in refueling stations of Ardabil city (Iran). Twenty-four refueling stations including 15 petrol and 9 compressed natural gas (CNG) stations from different regions were selected and monitored for ambient BTEX concentrations. Air samples were taken based on NIOSH Manual of Analytical Method no 1501. Target compounds were extracted using CS₂ and analyzed by GC equipped with FID. Average concentrations of benzene, toluene, ethylbenzene, and xylene were obtained 2.01, 1.80, 2.72, and 1.65 mg/m³, respectively. Benzene concentrations exceeded the occupational exposure limit set by the Iran Ministry of Health and Medical Education. Its concentrations were significantly higher in commercial areas (2.72 mg/m³) compared to suburban areas (1.89 mg/m³). BTEX concentrations in gasoline stations were slightly, but not significantly, higher than those in CNG stations. Long-term exposure cancer risk of 1884?×?10^?6?±?390?×?10^?6 and hazard index of 22.83?±?3.66 were estimated for benzene and BTEX compounds, respectively. The results declare the necessity for controlling BTEX emission (mainly benzene) and monitoring employee’s exposure in refueling stations.     

A study of groundwater contamination with organic fuels and potential public health impact in Itaguaí, Rio de Janeiro State,Brazil

Increasing attention is current focused on urban groundwater contamination with gasoline hydrocarbon compounds in Brazil. The compounds benzene, toluene, ethylbenzene, and xylenes (BTEX) contained in fuels are highly toxic and can have severe public health consequences, besides posing the risk of intake from the water table by way of contamination. After two years of a steady gasoline storage tank leak, water samples from private household wells in the district of Brisa Mar, Itaguaí, Rio de Janeiro State, were analyzed and the concentration of BTEX compounds was evaluated. Two out of ten water samples from the study area presented BTEX concentrations above the National Water Quality Standard (Brazilian Health Ministry Ruling No. 1469/2000), in which the maximum permissible benzene concentration is 5 micro g.L-1. Four others wells were also contaminated with nitrate, responsible for the induction of methemoglobinemia. Natural attenuation (intrinsic biodegradation) mechanisms through electron acceptors was also investigated in this study.     

Environmental exposure and children's health in China

Concerns regarding adverse health effects of exposure to environmental pollutants among children are increasing. This subject area is particularly important in China because of environmental pollution problems associated with rapid development and a large population. The authors provide what is, to their knowledge, the first review in China of English- and Chinese-language literature regarding the current status of environmental exposures to children in China and the impact of these exposures on the health of children. Children in China are exposed to diverse environmental pollutants, including traditional pollutants such as lead and mercury and emerging pollutants such as phthalates and perfluorinated compounds. Incidence and prevalence of certain childhood diseases have increased in last decades. In China, a limited number of data on environmental exposure and children's health are available, and further high-quality studies are needed.     

Human biomonitoring in Israel: past, present, future

The first human biomonitoring (HBM) studies in Israel in the 1970s and 80s focused on measuring exposure to polychlorinated biphenyls (PCBs) and organochlorine insecticides in the general population and organophosphate pesticides in agricultural workers. In the late 1990 s, a regional human biomonitoring study found differences in blood lead levels in children from Israel, Jordan, and the Palestinian Authority. Taken together with data on time trends in lead emissions in Israel, the study indicated the benefits from phasing out of leaded gasoline. More recently, a pilot study in pregnant women in Jerusalem, conducted in collaboration with the US-CDC, found widespread exposure to phthalates, organophosphate pesticides, and the carbamate bendiocarb. Creatinine-adjusted total dimethyl (DM) metabolite concentrations were between 4 and 6 times higher than populations of pregnant women in the United States. The Israel Ministry of Health is currently collaborating with the Hebrew University of Jerusalem and Al Quds University to study exposures to phthalates and organophosphates in pregnant women in Israel and the Palestinian Authority. The Israel Ministry of Health has also begun the first National Biomonitoring Study to measure exposures to bisphenol A, phthalates, organophosphates, polyaromatic hydrocarbons, the phytoestrogens genistein and daidzein, and cotinine in the Israeli adult population. This study is being carried out in collaboration with the University of Erlangen-Nuremberg in Germany. Until recently, HBM programs in Israel were targeted at selected occupational groups (workers potentially exposed to metals, volatile organic compounds (VOCs), and cholinesterase inhibitors) and naval divers potentially exposed to environmental contaminants. The future of HBM in Israel lies in extending such programs to measuring exposures in representative samples of the general population, increasing international collaboration in this field, developing analytical capacity and expertise, and increasing use of human biomonitoring studies in forming and evaluating environmental health policy.     

2006--2008年常熟市部分乡镇箱包企业苯作业工人外周血象分析

目的探讨常熟市箱包企业生产环境中存在的苯系物对作业工人健康的影响,为采取防护措施保护工人身体健康提供依据。方法检测各箱包企业工作场所中的苯系物浓度,对苯接触组以及对照组工人进行体检,检查外周血血红蛋白（Hb）、含量和白细胞（WBC）、血小板（PLT）计数。结果苯作业工人中外周血白细胞、血小板、血红蛋白下降人数明显高于对照组,其中自细胞计数下降差异最为明显,2006-2008年,各年接触组与对照组比较x^2值分别为11．88、22．87、17．49,均P〈0．01。结论长期从事苯作业的工人外周血液系统有较明显的改变,需要依法加强对苯作业工人的健康监护并改善劳动环境。