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[en] Years of life lost (YLL) is a more informative and accurate indicator than daily death counts for assessing air pollution related premature death. However, there is limited evidence available about the relationship of air pollution with YLL, especially in China. We conducted a ten-year (from January 1st, 2001 to December 31st, 2010) multi-district time-series study to estimate the effects of ambient particulate matter with an aerodynamic diameter of less than 10 μm in size (PM10) on daily non-accidental deaths and YLL in six districts of Tianjin, China. Meta-analysis was used to merge the results of the six districts. We found that the increase of PM10 was significantly associated with daily death and YLL in the six districts, except with the YLL in Heping district. 10 μg/m3 increases in PM10 were associated with the maximum increases in excess risk (ER) of death counts of 0.33% (95% confidence interval [CI]: 0.25%, 0.41%) at lag01 and in YLL of 0.80 (95%CI: 0.47, 1.13) person year at lag01 for the combined effects of six districts, respectively. Moreover, the associations of PM10 on daily death counts and YLL were stronger in the elder people (≥65 years) than those in the younger ones (<65 years). These findings may help to shed light on the policy-making of PM-control in China and provide useful information for the protection of susceptible population. - Highlights: • A more informative indicator (YLL) was used to assess PM10-related health effects. • A ten-year multi-county time-series study was conducted to assess effects of PM10. • PM10 was significantly associated with daily non-accidental death and YLL. • The associations were stronger in the elderly than that in the younger ones. • This study provides more convincing evidence for the policy-making of PM-control. - This ten-year time-series study showed that PM10 was significantly associated with daily non-accidental death and YLL.
[en] Dinitrotoluenes are used as propellants and in explosives by the military and as such have been found at relatively high concentrations in the soil. To determine whether concentrations of 2,4-dinitrotoluene (2,4-DNT) in soil are toxic to amphibians, 100 red-backed salamanders (Plethodon cinereus) were exposed to either 1500, 800, 200, 75 or 0 mg 2,4-DNT/kg soil for 28 days and evaluated for indicators of toxicity. Concentrations of 2,4-DNT were less than targets and varied with time. Most salamanders exposed to concentrations exceeding 1050 mg/kg died or were moribund within the first week. Salamanders exposed to soil concentrations exceeding 345 mg/kg lost >6% of their body mass though no mortality occurred. Overt effects included a reduction in feed consumption and an increase in bucco-pharyngeal oscillations in salamanders. These results suggest that only high soil concentrations of 2,4-DNT have the potential to cause overtly toxic effects in terrestrial salamanders. - Exposures of 2,4-dinitrotoluene in soil exceeding 345 mg/kg causes toxicity to P. cinereus
[en] Highlights: • The relationship between air pollution and respiratory disease is proposed. • Nonmalignant respiratory disease mortality was associated with PM10 and SO2. • Passive smokers are susceptible to the harmful effects of air pollution.
[en] Fine root dynamics (diameter < 1 mm) in mature Fagus sylvatica, with the canopies exposed to ambient or twice-ambient ozone concentrations, were investigated throughout 2004. The focus was on the seasonal timing and extent of fine root dynamics (growth, mortality) in relation to the soil environment (water content, temperature). Under ambient ozone concentrations, a significant relationship was found between fine root turnover and soil environmental changes indicating accelerated fine root turnover under favourable soil conditions. In contrast, under elevated ozone, this relationship vanished as the result of an altered temporal pattern of fine root growth. Fine root survival and turnover rate did not differ significantly between the different ozone regimes, although a delay in current-year fine root shedding was found under the elevated ozone concentrations. The data indicate that increasing tropospheric ozone levels can alter the timing of fine root turnover in mature F. sylvatica but do not affect the turnover rate. - Doubling of ozone concentrations in mature European beech affected the seasonal timing of fine root turnover rather than the turnover rate.
[en] The launch of China's new national urbanization plan, coupled with increasing concerns about air pollution, calls for better understandings of the nexus between urbanization and the air pollution–related health. Based on refined estimates of PM2.5 related mortality in China, we developed an Urbanization–Excess Deaths Elasticity (U–EDE) indicator to measure the marginal PM2.5 related mortality caused by urbanization. We then applied statistical models to estimate U–EDE and examined the modification effects of income on U–EDE. Urbanization in China between 2004 and 2012 led to increased PM2.5 related mortality. A 1% increase in urbanization was associated with a 0.32%, 0.14%, and 0.50% increase in PM2.5 related mortality of lung cancer, stroke, and ischemic heart disease. U–EDEs were modified by income with an inverted U curve, i.e., lower marginal impacts at the lowest and highest income levels. In addition, we projected the future U–EDE trend of China as a whole and found that China had experienced the peak of U–EDE and entered the second half of the inverted U–shaped curve. In the near future, national average U–EDE in China will decline along with the improvement of income level if no dramatic changes happen. However, the decreased U–EDE only implies that marginal PM2.5–related mortality brought by urbanization would decrease in China. Total health damage of urbanization will keep going up in the predictable future because the U–EDE is always positive. - Highlights: • Urbanization in China from 2004 to 2012 led to increased PM2.5 related mortality. • Income modified the marginal PM2.5 related mortality brought by urbanization. • Total PM2.5 related mortality of urbanization will keep going up in the future. • National industrial structure upgrade strategy will mitigate the mortality burdens.
[en] Chlorpyrifos (an insecticide) and chlorothalonil (a fungicide) are transported in stormwater runoff and can be lethal to receiving aquatic system biota. This study determined removal rates of chlorpyrifos and chlorothalonil in simulated stormwater runoff treated in constructed wetland mesocosms. Using sentinel species, Ceriodaphnia dubia and Pimephales promelas, observed declines in toxicity of the simulated runoff after treatment were 98 and 100%, respectively. First order removal rates were 0.039/h for chlorpyrifos and 0.295/h for chlorothalonil in these experiments. Constructed wetland mesocosms were effective for decreasing concentrations of chlorpyrifos and chlorothalonil in simulated stormwater runoff, and decreasing P. promelas and C. dubia mortality resulting from these exposures. The results from this study indicate that constructed wetlands could be part of an efficient mitigation strategy for stormwater runoff containing these pesticides. - Constructed wetlands have potential for treatment of pesticide mixtures in stormwater runoff
[en] Effects of field application levels of wildfire control chemicals, Phos-Chek[reg] G75-F (PC) and Silv-Ex[reg] (SE), were examined on red-winged blackbird (Agelaius phoeniceus) embryos. Embryos were more sensitive to PC and SE when eggs were immersed for 10 s at an early developmental stage (days 3-5 of incubation) than at a later stage (days 6-9 of incubation). The LC50 (concentration causing 50% mortality) for early stage embryos exposed to PC was 213.3 g/L (slope = 1.6; 95% confidence interval [CI] = 129.1-326.1). The no observed effect concentration (NOEC) was below 135 g PC/L, which caused a significant increase in embryonic mortality and represents the lowest field coverage level of 1 gal/100 feet2. The LC50 for early stage embryos exposed to SE was 19.8 g/L (slope = 1.5; 95% CI = 11.7-52.2). Significant mortality was observed at 10 g SE/L and marginal at 7.5 g SE/L with an apparent NOEC around 5 g SE/L. Neither chemical resulted in apparent developmental malformations. - Embryos of songbirds are potentially at risk from the wildfire control chemicals, Phos-Chek[reg] G75-F and Silv-Ex[reg]
[en] Cylindrospermopsis raciborskii is a cyanobacterium responsible for the production of the toxin, cylindrospermopsin (CYN). Tadpoles of the cane toad Bufo marinus were exposed to freeze-thawed whole cell extracts or live cultures of C. raciborskii containing maximum CYN concentrations of 400 μg L-1 or 232 μg L-1, respectively. Exposure to live culture treatment solutions resulted in up to 66% mortality of B. marinus, whereas tadpoles exposed to whole cell extracts containing similar toxin concentrations survived. Decreases in relative growth rates and time spent for swimming were recorded from tadpoles during both types of exposure regimes. Bioconcentration of CYN was not evident following exposure to whole cell extracts containing extracellular toxin. In contrast exposure to live cultures, which contained cell-bound toxin, resulted in maximum average tissue concentrations of 895 μg free-CYN kg-1 fresh weight. This is the first investigation of C. raciborskii exposure effects and toxin bioaccumulation in the developmental stages of an amphibian. - Cane toad tadpoles experienced adverse effects and bioaccumulation of toxin following exposure to the cyanobacterium Cylindrospermopsis raciborskii
[en] This study, framed within geographical epidemiology, presents preliminary findings concerning the association between the concentrations of chemical elements obtained through atmospheric biomonitoring with lichens and cancer mortality in the Portuguese population. Exploratory analyses were performed to identify potential confounders for the relationships between chemical elements and neoplasm mortality and to assess the extent of their interference. The results of this study highlight some methodological and conceptual difficulties inherent to observational and geographical studies, in the specific context of the Portuguese population, and the challenge posed by the large numbers of pollutants considered. - Relationship between chemical elements and mortality from neoplasms in the Portuguese population and the effect of confounders
[en] Background: Although animal data have suggested the carcinogenic activity of trihalomethanes (THMs), there is inconsistent evidence supporting the link between THM exposure and cancers in humans. Objectives: We investigated the association between specific and total blood THM levels with the risk of total cancer mortality in adults. Methods: We analyzed data from the 1999–2004 Third National Health and Nutrition Examination Survey and the Linked Mortality File of the United States. A total of 933 adults (20–59 years of age) with available blood THM levels and no missing data for other variables were included. Four different THM species (chloroform, bromodichloromethane (BDCM), dibromochloromethane (DBCM) and bromoform) were included, and the codes associated with cancer (malignant neoplasm) were C00 through C97, based on the underlying causes of death listed in the International Classification of Disease 10the Revision. Results: Compared with adults in the lowest DBCM, bromoform, and total brominated THM tertiles, those in the highest DBCM, bromoform, and total brominated THM tertiles exhibited adjusted hazard ratios (HR) of total cancer mortality of 4.97 (95% confidence interval (CI) = 1.59–15.50), 4.94 (95% CI = 1.56–15.61), and 3.42 (95% CI = 1.21–15.43) respectively. The risk of total cancer mortality was not associated with increases in blood chloroform and total THM levels. Conclusions: We found that the baseline blood THM species, particularly brominated THMs, were significantly associated with total cancer mortality in adults. Although this study should be confirm by other studies, our findings suggest a possible link between THM exposures and cancer. - Highlights: • Trihalomethanes (THM) are classified as either probable or possible carcinogens. • Limited evidence on the link between THM and the incidence of cancer in humans. • We investigated the association between blood THM levels and the risk of total cancer mortality. • High blood THM levels are associated with a high risk of cancer mortality in adults. • Our findings suggest a possible link between exposure to brominated THM and cancer in humans. - Blood trihalomethanes levels, particularly brominated THMs, were significantly associated with total cancer mortality in adults.