Environmental noise is a growing and well recognized health problem. However, in many cases people are exposed not to a single noise source-for example, road, railway, or aircraft noise-but to a combination of noise exposures and there is only limited knowledge of the effects on health of exposure to combined noise sources. A socio-acoustic survey among 1953 persons aged 18-75 years was conducted in residential areas exposed to railway and road traffic noise with sound levels ranging from L(Aeq,24h) 45-72 dB in a municipality east of Gothenburg, Sweden. The objectives were to assess various adverse health effects, including annoyance, and to elucidate the impact of exposure to single and combined noise sources. In areas exposed to both railway and road traffic, the proportion annoyed by the total traffic sound environment (total annoyance) was significantly higher than in areas with one dominant noise source (rail or road traffic) with the same total sound exposure (L(Aeq,24h,tot)). This interaction effect was significant from 59 dB and increased gradually with higher sound levels. Effects of the total sound exposure should be considered in risk assessments and in noise mitigation activities.
OBJECTIVE: We investigated if asphalt workers showed signs of lung epithelial injury as shown by increased Clara cell protein 16 (CC16) in serum after 6 months of exposure. METHODS: Asphalt pavers, asphalt plant operators, and asphalt engineers underwent lung function tests and blood samples before the start of the asphalt season. The tests were repeated before the end of the asphalt season. Blood samples were analyzed for concentration of CC16 and interleukin-6 (IL-6). RESULTS: After adjustment for current smoking, the pavers had a significantly larger increase in CC16 concentrations after the season as compared with that of the engineers and plant operators. In pavers, the change in serum CC16 was correlated with the change in IL-6. CONCLUSION: CC16 increased over the season in pavers and appears to be a useful biomarker for lung epithelial injury in exposed workers.
Oxidative Stress and Inflammation, Department of Public Health and Caring Sciences, Faculty of Medicine, Uppsala University, Uppsala Science Park, and Center of Excellence-Inflammation, Uppsala University Hospital, Uppsala, Sweden.
Oxidative stress is assumed to be the key underlying factor in the pathogenesis of many common diseases. This study describes the basal levels of 8-iso-PGF(2alpha ), a major F(2)-isoprostane and an in vivo oxidative stress biomarker in healthy subjects from three countries, namely Italy, Poland and Sweden, in relation to their smoking habits, age and gender. It studied urinary 8-iso-PGF(2alpha ) in 588 subjects from Sweden (n=220), Italy (n=203) and Poland (n=165). Polish subjects had the highest levels of F(2)-isoprostanes followed by the Swedish and Italians when adjusted for smoking, age, sex and creatinine and the inter-country differences were statistically significant. Smokers had significantly higher levels of 8-iso-PGF(2alpha ) compared to non-smokers in all countries and there was a moderate decrease with age. Women had only slightly lower 8-iso-PGF(2alpha ) than men. There is a difference in F(2)-isoprostane levels in vivo between countries. Smoking, age and gender affect isoprostane formation and should be taken into consideration in clinical studies of oxidative stress.
We conducted a cross-sectional study in Sweden, Italy and Poland to assess environmental and occupational exposure to mercury from chloralkali (CA) plants and the potential association with biomarkers of early renal dysfunction. Questionnaire data and first-morning urine samples were collected from 757 eligible subjects. Urine samples were analysed for mercury corrected for creatinine (U-HgC), alpha-1-microglobulin (A1M), N-acetyl-beta-glucosaminidase (NAG) and albumin. Determinants of urinary mercury excretion were examined. Levels of kidney markers were compared in three U-HgC categories, and differences were tested taking age and other covariates into account. In the general population, the median U-HgC was higher in Italian (1.2 microg/gC) than in Polish (0.22 microg/gC) or Swedish (0.21 microg/gC) subjects, and no effect of living close to CA plants could be shown. Dental amalgam, chewing on amalgam, and fish consumption were positively associated with U-HgC. In subjects from the general population, no effects on the kidney markers could be detected, while in men, including workers occupationally exposed to mercury, U-HgC was positively associated with the kidney markers, especially with NAG, but to some extent also with A1M and albumin. Differences in urinary mercury and kidney markers in the general population between three studied countries could possibly be due to dietary factors, increased susceptibility to mercury at low selenium intake or co-exposure to other nephrotoxic metals.
As part of the European Mercury Emissions from Chlor Alkali Plants (EMECAP) project, we tested the hypothesis that contamination of ambient air with mercury around chlor alkali plants using mercury cells would increase the internal dose of mercury in people living close to the plants. Mercury in urine (U-Hg) was determined in 225 individuals living near a Swedish or an Italian chlor alkali plant, and in 256 age- and sex-matched individuals from two reference areas. Other factors possibly affecting mercury exposure were examined. Emissions and concentrations of total gaseous mercury (TGM) around the plants were measured and modeled. No increase in U-Hg could be demonstrated in the populations living close to the plants. This was the case also when the comparison was restricted to subjects with no dental amalgam and low fish consumption. The emissions of mercury to air doubled the background level, but contributed only about 2 ng/m(3) to long-term averages in the residential areas. The median U-Hg levels in subjects with dental amalgam were 1.2 microg/g creatinine (micro/gC) in Italy and 0.6 microg/gC in Sweden. In individuals without dental amalgam, the medians were 0.9 microg/gC and 0.2 microg/gC, respectively. The number of amalgam fillings, as well as chewing, fish consumption, and female sex were associated with higher U-Hg. The difference between the countries is probably due to higher fish consumption in Italy, demethylated methyl mercury (MeHg) being partly excreted in urine. Post hoc power calculations showed that if the background mercury exposure is low it may be possible to demonstrate an increase in U-Hg of as little as about 10 ng/m(3) as a contribution to ambient mercury from a point source.