Exposure to preservatives used in the industrial pre-treatment of timber.
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OBJECTIVE: The research was to survey potential dermal exposure and inhalation exposure of operators to preservative fluids used in industrial timber pre-treatment. RESULTS: Surveys in 1996-98 produced 64 data points. These were taken from 54 sites, and involved 57 timber pre-treatment process operators. Of the data, 38 related to copper chromium arsenic preservative used in vacuum-pressure processes, 19 to solvent-based preservative in double vacuum processes and 7 to water-based preservative in double vacuum processes. Treatment cycle times, preservative concentrations, treatment load sizes and quantities of preservative used per cubic metre of timber are reported. Preservative deposition patterns were similar for all treatments, with about 90% on the legs, and most of the remainder on the arms and chest. The results are quoted as mg preservative preparation (as opposed to active substance), expressed as mg per treatment cycle and mg per minute. Water-based products in vacuum-pressure processes (38 data) showed potential dermal exposure in the range 547-132,000 mg per cycle with a median value 3960 mg per cycle (median cycle time 3 h). Water-based products in double vacuum processes (7 data) showed a range 59-8750 mg per cycle with a median value 4260 mg per cycle; and solvent-based products in double vacuum processes (19 data) showed a range 7.5-449 mg per cycle with a median value 119 mg per cycle (median cycle time 1 h for double-vacuum processes). Contamination of work clothing occurred in nearly all surveys, with around 10% penetration of the preservative as estimated by a sampling patch mounted inside the operator's coveralls. Contamination was measured inside the operator's gloves in nearly all surveys. Wearing fresh gloves was found to reduce exposure to arsenic by 71% and to permethrin by 37%. Contamination on socks was measured and found to be less frequent for double vacuum than for vacuum-pressure processes. Exposure by inhalation for vacuum-pressure processes expressed as preservative, showed a range of 0.06-7.96 mg/m3, with a median value of 1.07 mg/m3, time-weighted average exposure over one or two treatment cycles. Exposure was detected in 68% of the vacuum-pressure process surveys. There was evidence for aerosol generation on transporting timber treated with water-based preservative. For double vacuum processes, two non-zero results only were found, both for water-based preservatives. Aerosols within treatment vessels were found to have dispersed 2.5 min after opening the door. Pilotstudy biological monitoring data for urinary chromium, arsenic, and permethrin metabolites are quoted with reference to creatinine. There are tentative conclusions relating to up take via the skin. (+info)
Semen quality and reproductive endocrine function in relation to biomarkers of lead, cadmium, zinc, and copper in men.
(50/1312)
Blood lead (BPb), activity of delta-aminolevulinic acid dehydratase (ALAD), erythrocyte protoporphyrin (EP), blood cadmium (BCd), serum zinc (SZn), seminal fluid zinc (SfZn), serum copper (SCu), and parameters of semen quality and of reproductive endocrine function were measured in 149 healthy male industrial workers 20-43 years of age. The group contained 98 subjects with slight to moderate occupational exposure to Pb and 51 reference subjects. All of the subjects lived in Zagreb, Croatia. Significant (p < 0.05) correlations of BPb, ALAD, and/or EP with reproductive parameters indicated a Pb-related decrease in sperm density, in counts of total, motile, and viable sperm, in the percentage and count of progressively motile sperm, in parameters of prostate secretory function (SfZn, acid phosphatase, and citric acid in seminal fluid), and an increase in abnormal sperm head morphology, serum testosterone, and estradiol. These associations were confirmed by results of multiple regression, which also showed significant (p < 0. 05) influence of BCd, SZn, SCu, smoking habits, alcohol consumption, or age on certain reproductive parameters. These effects were mainly of lower rank and intensity as compared to Pb-related reproductive effects, whereas BCd contributed to a decrease in sperm motility and an increase in abnormal sperm morphology and serum testosterone. No significant Pb- or Cd-related influence was found on levels of the lactate dehydrogenase isoenzyme LDH-C(4) and fructose in seminal fluid or on follicle-stimulating hormone, luteinizing hormone, and prolactin in serum. The seminal fluid concentrations of Pb (SfPb) and Cd (SfCd) were measured in 118 of the 149 subjects, and a highly significant (p < 0.0001) correlation was found between BPb and SfPb levels (r = 0.571) and between BCd and SfCd levels (r = 0.490). The overall study results indicate that even moderate exposures to Pb (BPb < 400 microg/L) and Cd (BCd < 10 microg/L) can significantly reduce human semen quality without conclusive evidence of impairment of male reproductive endocrine function. (+info)
The role of selenium in iodine metabolism in children with goiter.
(51/1312)
Possible interactions between selenium and iodine metabolism were investigated in 7- to 16-year-old children with goiter (n = 136) living in southeastern Poland in iodine-deficient areas influenced by a sulfur industry. The Se-iodine interactions in these children were compared to the interactions in children from outside of that region (n = 38). Blood selenium (BSe) concentration and plasma glutathione peroxidase activity were much lower in the study group (64.1 +/- 15.7 microg/L; 111.0 +/- 27.6 U/L) than in the control group (85.3 +/- 19.6 microg/L; 182.4 +/- 35.6 U/L). Almost all of the data [plasma thyroid-stimulating hormone (TSH) concentration, plasma free thyroxine (fT(4)) concentration] fell within the reference limits. There was no statistically significant difference between the control and the study groups with respect to fT(4) and TSH. However, statistically significant differences of fT(4) and TSH in the study group were revealed between females belonging to the lower (n = 21; fT(4), 16.1 +/- 3.3 pmol/L; TSH, 1.83 +/- 1.05 mU/L) and upper Se quartiles (n = 24; fT(4), 14.5 +/- 2.2 pmol/L; TSH, 1. 26 +/- 0.90 mU/L), p < 0.05. Neither group differed in iodine in urine concentration, age, and body mass index. The difference in fT(4) concentrations can be attributed to an Se deficiency. The relationship exists only for females, which suggests a sex-linked hormonal response to concomitant Se and iodine deficiencies. (+info)
"Cater to the children": the role of the lead industry in a public health tragedy, 1900-1955.
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A major source of childhood lead poisoning, still a serious problem in the United States, is paint. The dangers of lead were known even in the 19th century, and the particular dangers to children were documented in the English-language literature as early as 1904. During the first decades of the 20th century, many other countries banned or restricted the use of lead paint for interior painting. Despite this knowledge, the lead industry in the United States did nothing to discourage the use of lead paint on interior walls and woodwork. In fact, beginning in the 1920s, the Lead Industries Association and its members conducted an intensive campaign to promote the use of paint containing white lead, even targeting children in their advertising. It was not until the 1950s that the industry, under increasing pressure, adopted a voluntary standard limiting the amount of lead in interior paints. (+info)
Carbon monoxide poisoning associated with use of LPG-powered (propane) forklifts in industrial settings--Iowa, 1998.
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In 1998, the Iowa Department of Public Health (IDPH) and Iowa State University (ISU) Extension Department, with the assistance of local health departments, investigated a series of carbon monoxide (CO) poisonings associated with the use of liquified petroleum gas (LPG)-powered forklifts in light industry. In each episode, forklifts emitting high CO concentration levels were operated in inadequately ventilated warehouse and production facilities, which resulted in high CO accumulations. Employees at each site developed symptoms of CO poisoning, and some employees received inadequate or inappropriate medical care. This report summarizes the investigations and provides recommendations to prevent such incidents. (+info)
Occupational lung cancer risk for men in Germany: results from a pooled case-control study.
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Occupational exposures such as crystalline silica, diesel engine exhaust, polycyclic aromatic hydrocarbons, and man-made mineral fibers are strongly suspected to increase lung cancer risk. Two case-control studies in Germany conducted between 1988 and 1996 were pooled for a joint analysis. A total of 3,498 male cases and 3,541 male population controls, frequency matched for age and region, were included in the study. The lifelong history of all jobs and industries was coded and occupational exposures were evaluated by expert rating. Odds ratios, crude and adjusted for smoking and asbestos exposure, were calculated by conditional logistic regression. Job-related evaluation showed a statistically significant increased odds ratio adjusted for smoking among farmers; forestry workers, fishermen, and livestock workers; miners and quarrymen; chemical processors; cabinet makers and related wood workers; metal producers and processors; bricklayers and carpenters; road construction workers, pipelayers and well diggers; plasterers, insulators, and upholsterers; painters and lacquerers; stationary engine and heavy equipment operators; transport workers and freight handlers; and service workers. With regard to specific occupational exposures, elevated odds ratios (OR) (95% confidence intervals (CI)) for lung cancer risk adjusted for smoking and asbestos exposure were observed for man-made mineral fibers (OR = 1.48, 95% CI 1.17, 1.88); crystalline silica (OR = 1.41, 95% CI 1.22, 1.62); diesel engine exhaust (OR = 1.43, 95% CI 1.23, 1.67); and polycyclic aromatic hydrocarbons (OR = 1.53, 95% CI 1.14, 2.04). The risk of asbestos exposure, adjusted for smoking was also increased (OR = 1.41, 95% CI 1.24, 1.60). (+info)
Multiplex PCR for detection and identification of lactococcal bacteriophages.
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Three genetically distinct groups of Lactococcus lactis phages are encountered in dairy plants worldwide, namely, the 936, c2, and P335 species. The multiplex PCR method was adapted to detect, in a single reaction, the presence of these species in whey samples or in phage lysates. Three sets of primers, one for each species, were designed based on conserved regions of their genomes. The c2-specific primers were constructed using the major capsid protein gene (mcp) as the target. The mcp sequences for three phages (eb1, Q38, and Q44) were determined and compared with the two available in the databases, those for phages c2 and bIL67. An 86.4% identity was found over the five mcp genes. The gene of the only major structural protein (msp) was selected as a target for the detection of 936-related phages. The msp sequences for three phages (p2, Q7, and Q11) were also established and matched with the available data on phages sk1, bIL170, and F4-1. The comparison of the six msp genes revealed an 82. 2% identity. A high genomic diversity was observed among structural proteins of the P335-like phages suggesting that the classification of lactococcal phages within this species should be revised. Nevertheless, we have identified a common genomic region in 10 P335-like phages isolated from six countries. This region corresponded to orfF17-orf18 of phage r1t and orf20-orf21 of Tuc2009 and was sequenced for three additional P335 phages (Q30, P270, and ul40). An identity of 93.4% within a 739-bp region of the five phages was found. The detection limit of the multiplex PCR method in whey was 10(4) to 10(7) PFU/ml and was 10(3) to 10(5) PFU/ml with an additional phage concentration step. The method can also be used to detect phage DNA in whey powders and may also detect prophage or defective phage in the bacterial genome. (+info)
Economic activity and congenital anomalies: an ecologic study in Argentina. ECLAMC ECOTERAT Group.
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In this study, we analyze the association between industrial activity and the occurrence of 34 congenital anomalies. We selected 21 counties in Argentina during 1982-1994 and examined a total of 614,796 births in these counties in consecutive series. We used the International Standard Industrial Classification of All Economic Activities (United Nations, 1968) as an indicator of exposure to 80 specific industrial activities. Incidence rate ratios for each congenital anomaly were adjusted by the socioeconomic level of the county according to a census index of social deprivation. For a given exposure/anomaly association to be considered as significant and relevant, the exposure had to be a statistically significant risk for the occurrence of the anomaly and an increase in the birth prevalence rate of the congenital anomaly type involved had to be observed in those counties where the putative causal activity was being performed. Significant associations (p < 0.01) were identified between textile industry and anencephaly, and between the manufacture of engines and turbines and microcephaly. These observations are consistent with previous reports on occupational exposure, and their further investigation by means of case-control studies is recommended. (+info)