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House dust and airborne particles (PM) were sampled before (T1) and 1 day (T2), 4-6 months (T3) as well as 10-12 months (T4) after a pest control operation (PCO). Cyfluthrin was applied in 11, cypermethrin in 1, deltamethrin in three and permethrin in four interiors. The pyrethroid concentrations in house dust and PM were measured by GC/MS with a detection limit for all pyrethroids of 0.5 mg/kg house dust and of 1 ng/m3 PM for deltamethrin and permethrin and 3 ng/m3 PM for cyfluthrin and cypermethrin. A general background concentration of permethrin (95th percentile: 5.9 mg/kg) and cyfluthrin (95th percentile: 34.9 mg/kg) in house dust was found. In general, an appropriately performed PCO lead to an increase of pyrethroids in house dust as well as in PM, in some cases up to 1 year after application. One day after the application the cyfluthrin concentration increased significantly from 0.25 (T1) to 33.8 mg/kg house dust (T2) and up to 4.9 ng/m3 in PM. The permethrin concentration increased significantly from 4.3 to 70 mg/kg in house dust and up to 18.1 ng/m3 in PM, deltamethrin increased to 54.5 mg/kg and 20.8 ng/m3 and cypermethrin to 14 mg/kg and 45.7 ng/m3. Thereafter a continuous decrease could be observed during the time course of 1 year. After 1 year the permethrin concentration in house dust was still 1/5 of the T2 concentration, whereas for cypermethrin and cyfluthrin only 1/14 and 1/23 of the T2 concentration were found. Deltamethrin was not detected at all after T2. Moreover, the data of this study showed significant, positive correlations between pyrethroids in house dust and in airborne particles especially one day after PCO.

In order to investigate human's exposure to permethrin from treated woollen textile floor coverings and possible adverse health effects, a study was carried out in 80 private homes in Hannover (Germany) equipped with woollen textile floor coverings (wool wall-to-wall carpets or woven or knotted rugs). For indoor monitoring, permethrin was determined both in house dust and on suspended particles. While permethrin concentrations in house dust (< 2 mm) were high (arithmetic mean: 53.7 mg/kg, 90th percentile 129.1 mg/kg), the permethrin concentrations in the air (suspended particles) were very low (arithmetic mean 2.8 ng/m3, 90th percentile 5.8 ng/m3, first sampling). Additional experiments demonstrate that permethrin on suspended particles result from carpet fiber abrasion (and not from an evaporation/re-condensation process). The internal exposure of the 145 inhabitants participating in the study was determined by biological monitoring (permethrin metabolites in urine). In a first sampling period almost 14% of the samples showed concentrations of the metabolite DCCA and almost 23% of the metabolite 3-PBA above the limit of detection (0.2 microgram/l). A model was developed which allows the calculation of the metabolite concentration in urine due to inhalative uptake of permethrin. Even for the worst case situation the calculated metabolite concentrations were ca. 30 times lower than the experimental results. The observed concentrations of metabolites are comparable to those of the background concentrations of the general population in Germany, suggesting that they must origin from other sources than woollen textile floor coverings. The indoor and biological monitoring data as well as the evaluation of the reported symptoms give no indication of an adverse health effect due to carpet treatment by permethrin.

Chrysanthemate insecticides like (S)-bioallethrin, natural pyrethins, and related pyrethroids are subjected to extensive hydrolytic and oxidative degeneration by the mammalian metabolism, leading to a complex series of metabolites partially conjugated and finally eliminated in the urine. The major oxidation products of chrysanthemic acid, cis-(E)- and trans-(E)-chrysanthemumdicarboxcylic acid (cis-(E) and trans-(E)-CDCA), were synthesized and their structures were established by nuclear magnetic resonance spectrometry (H1-NMR) and mass spectrometry (MS). Diastereoselective separation was by high performance liquid chromatography (HPLC) and capillary gas chromatography (GC). An analytical method for extraction and identification of CDCA from human urine was developed. Quantitation was by gas chromatography and electron-impact mass spectrometry (GC/MS). The limit of detection was 20 microg/l for cis-(E)-CDCA and 10 microg/l for trans-(E)-CDCA. To test the applicability of the presented method, urine samples of humans exposed to (S)-bioallethrin were investigated. Urinary peak excretion of trans-(E)-CDCA occurred within 24 h after exposure.

Based on numerous publications dealing with the effects of microbial emissions on workers in waste processing plants and on few papers concerning the assessment of the environmental health relevance of microbial aerosols on people living in the vicinity of composting facilities, the current state of the art in this field is presented. With regard to occupational exposure the possible health effects like infections, toxicity and allergies are specified. Since to date only few studies have been made of populations exposed to microbial aerosols in ambient air, the environmental health aspects are reviewed in the context of a study of three compost plants in Hesse, where ambient air measurements as well as epidemiological investigations were carried out. Final recommendations are given and the research needs regarding the environmental health significance of microbial aerosols are formulated.

The objective of this study was to perform biological monitoring of subjects who are occupationally exposed to pyrethroids. The study group consisted of 30 pest control operators exposed to cyfluthrin, cypermethrin or permethrin. After exposure, 24-h urine samples were collected and 20 ml of blood was drawn. The pyrethroid metabolites cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid, 3-phenoxybenzoic acid and fluorophenoxybenzoic acid were determined in the urine samples (limit of detection: 0.5 micrograms/l) by GC MS and the pyrethroids in plasma (limit of detection: 5 micrograms) GC-ECD. The concentrations of metabolites in the urine of the pest control operators ranged between < 0.5 micrograms/l and 277 micrograms/l urine. The concentrations of cyfluthrin, cypermethrin and permethrin in the plasma were below the limits of detection (< 5 micrograms/l). To test if the metabolites are specific for pyrethroid exposure, they were determined in the urine of non-exposed subjects (n = 40). In no case could pyrethroid metabolites be detected. A cyfluthrin elimination experiment showed that cyfluthrin metabolites are eliminated following first-order kinetics (t 1/2 = 6.4 h). Storage experiments demonstrate that frozen urine samples (-21 degrees C) show no significant losses of metabolites within a year. In contrast, pyrethroids stored in plasma are susceptible to further biodegeneration.

The reliability of human scalp hair as an indicator of mercury vapour exposure is contentious. In this study mercury concentrations in hair were compared with those in blood and urine of 20 dental students during their first "occupational" exposure to mercury vapour. Samples were collected before, at the end of the technical course of operating dentistry which lasted 6 weeks, and 3 months later. Mercury was measured by cold vapour atomic absorption spectrometry. In all biological media studied, mercury levels significantly (P < 0.05) reflected exposure to mercury vapour. After the time period without exposure mercury content decreased. Hair mercury levels were correlated to those in erythrocytes at sampling times 1 and 3 (r = 0.686 and r = 0.492) and to the frequency of fish consumption at sampling time 1. It is concluded that hair may be used as an indicator of internal uptake of mercury provided that it was not externally exposed to mercury vapour. In cases of occupational exposure to mercury vapour, hair is an useful tool for monitoring external exposure.

Due to their low mammalian toxicity but high insectical activity, pyrethroids are increasingly used for pest control. The objective of the present study was the development of a biological monitoring program to determine exposure to pyrethroids. A diastereoselective detection of the major pyrethroid metabolites cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid, cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylic acid, 3-phenoxybenzoic acid and fluorophenoxybenzoic acid by capillary gas chromatography in combination with mass selective detection was applied. The limits of determination ranged between 0.5 and 1 microgram/l urine, depending on the metabolite concerned. It was demonstrated that pyrethroid metabolites were detectable in urine for a period of elimination up to 3.5 days after exposure to cyfluthrin. Fluorophenoxybenzoic acid was shown to be a suitable biomarker for exposure to cyfluthrin. The presented method was adequate for monitoring pyrethroids in occupationally exposed subjects.

The present study aimed to investigate immune parameters in sera of adult persons chronically exposed to different degrees of ambient air pollution. As related to air pollution derived from coal mining industry and coke plants, a significantly increased prevalence of cases with abnormally high serum levels of the immunoglobulins IgA and IgM as well as the complement component C3c was found as compared with a less polluted control area, indicating a higher stimulation of acute reactants in combination with a polyclonal immune response. These findings may be attributed to elevated concentrations of airborne particulates, suggesting that permanent exposure to increased levels of airborne particulates leads to chronic irritation of the airways in association with activation of the immune system, which may give rise to an enhanced risk for chronic airway diseases.

Hair analysis comprises the determination of minerals, trace elements and drugs. It is applied in Germany with increasing frequency in the recently established field of environmental medicine for biological monitoring of the internal metal/metalloid exposure. Besides a number of advantages hair analysis is impaired by the difficulty-to distinguish between endogenous and exogenous sources of metals in hair. Except for methylmercury, there are no critical limit values for trace elements in hair available. However, valid reference values for some metals and for nicotine in hair have been recently presented in the German Environmental Survey. The significance of selected substances in hair are as follows: Aluminium in hair is of no value in environmental medicine. For assessment of cadmium and inorganic arsenic exposure hair analysis is only suitable as a screening method based on large populations. Monitoring of lead in hair is a valuable screening method also for small groups, especially for children. Based on toxicokinetics and under consideration of practicability the optimal biomarker of methylmercury exposure is the hair concentration. For other mercury compounds hair analysis is of lower significance. Nicotine and cotinine measurements in hair provide a practical and proper method for estimating environmental tobacco smoke exposure and to validate smoker status in epidemiological studies.

Pyrethroids are increasingly used indoors, because of their low mammalian toxicity but high insecticidal activity. Indoor application of pyrethroids, which is often carried out without adequate expert knowledge, may lead to high pesticide residues, often combined with health hazards for the people concerned. Objective of the present study is the development of a method for a biological monitoring to determine internal exposure to pyrethroids. Major pyrethroid metabolites were detected in urine by capillary gas chromatography in combination with mass selective detection (MSD). For the metabolites, the limits of determination range between 0.5 and 1 microgram/L urine. Our results so far demonstrate the detectability of cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (DVCA) and 3-phenoxybenzoic acid (3-PBA) in urine during a period of elimination of 48 hours after exposure to cypermethrin. In this paper the method is exemplary illustrated by one exposed person (pest control operator).