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A quantitative microbial risk assessment model for total coliforms and E. coli in surface runoff following application of biosolids to grassland
2017
Clarke, Rachel | Peyton, Dara | Healy, Mark G. | Fenton, O. (Owen) | Cummins, Enda
In Ireland, the land application of biosolids is the preferred option of disposing of municipal sewage waste. Biosolids provide nutrients in the form of nitrogen, phosphorus, potassium and increases organic matter. It is also an economic way for a country to dispose of its municipal waste. However, biosolids may potentially contain a wide range of pathogens, and following rainfall events, may be transported in surface runoff and pose a potential risk to human health. Thus, a quantitative risk assessment model was developed to estimate potential pathogens in surface water and the environmental fate of the pathogens following dilution, residence time in a stream, die-off rate, drinking water treatment and human exposure. Surface runoff water quality data was provided by project partners. Three types of biosolids, anaerobically digested (AD), lime stabilised (LS), and thermally dried (TD)) were applied on micro plots. Rainfall was simulated at three time intervals (24, 48 and 360 h) following land application. It was assumed that this water entered a nearby stream and was directly abstracted for drinking water. Consumption data for drinking water and body weight was obtained from an Irish study and assigned distributions. Two dose response models for probability of illness were considered for total and faecal coliform exposure incorporating two different exposure scenarios (healthy populations and immuno-compromised populations). The simulated annual risk of illness for healthy populations was below the US EPA and World Health Organisation tolerable level of risk (10⁻⁴ and 10⁻⁶, respectively). However, immuno-compromised populations may still be at risk as levels were greater than the tolerable level of risk for that subpopulation. The sensitivity analysis highlighted the importance of residence time in a stream on the bacterial die-off rate.
Show more [+] Less [-]Evaluation of short-term mortality attributable to particulate matter pollution in Spain
2017
Ortiz, Cristina | Linares, Cristina | Carmona, Rocio | Diaz, Julio
According to the WHO, 3 million deaths are attributable to air pollution due to particulate matter (PM) world-wide. However, there are no specific updated studies which calculate short-term PM-related cause specific mortality in Spain. The objective is to quantify the relative risks (RRs) and attributable risks (ARs) of daily mortality associated with PM10 concentrations, registered in Spanish provinces and to calculate the number of PM-related deaths. We calculated daily mortality due to natural (ICD-10: A00 R99), circulatory (ICD-10: I00 I99) and respiratory causes (ICD-10: J00 J99) for each province across the period 2000–2009. Mean daily concentrations of PM10, NO2 and O3 was used. For the estimate of RRs and ARs, we used generalised linear models with a Poisson link. A meta-analysis was used to estimate RRs and ARs in the provinces with statically significant results. The overall RRs obtained for these provinces, corresponding to increases of 10 μ g/m³ in PM10 concentrations were 1.009 (95% CI: 1.006 1011) for natural, 1.026 (95% CI: 1.019 1033) for respiratory, and 1.009 (95% CI: 1.006 1012) for circulatory-cause mortality. This amounted to an annual overall total of 2683 deaths (95% CI: 852 4354) due to natural, 651 (95% CI: 359 1026) due to respiratory, and 556 (95% CI: 116 1012) due to circulatory causes, with 90% of this mortality lying below the WHO guideline values. This study provides an updated estimate of the effect had by this type of pollutant on causes of mortality, and constitutes an important basis for reinforcing public health measures.
Show more [+] Less [-]Impact of partial fuel switch on household air pollutants in sub-Sahara Africa
2017
Tumwesige, Vianney | Okello, Gabriel | Semple, Sean | Smith, Jo
Over 700 million people in Sub-Saharan Africa depend on solid biomass fuel and use simple cookstoves in poorly ventilated kitchens, which results in high indoor concentrations of household air pollutants. Switching from biomass to biogas as a cooking fuel can reduce airborne emissions of fine particulate matter (PM2.5) and carbon monoxide (CO), but households often only partially convert to biogas, continuing to use solid biomass fuels for part of their daily cooking needs. There is little evidence of the benefits of partial switching to biogas. This study monitored real-time PM2.5 and CO concentrations in 35 households in Cameroon and Uganda where biogas and firewood (or charcoal) were used. The 24 h mean PM2.5 concentrations in households that used: (1) firewood and charcoal; (2) both firewood (mean 54% cooking time) and biogas (mean 46% cooking time); and (3) only biogas, were 449 μg m⁻³, 173 μg m⁻³ and 18 μg m⁻³ respectively. The corresponding 24 h mean CO concentrations were 14.2 ppm, 2.7 ppm and 0.5 ppm. Concentrations of both PM2.5 and CO were high and exceeded the World Health Organisation guidelines when firewood and charcoal were used. Partially switching to biogas reduced CO exposure to below the World Health Organisation guidelines, but PM2.5 concentrations were only below the 24 h recommended limits when households fully converted to biogas fuel. These results indicate that partial switching from solid fuels to biogas is not sufficient and continues to produce concentrations of household air pollution that are likely to harm the health of those exposed. Programmes introducing biogas should aim to ensure that household energy needs can be fully achieved using biogas with no requirement to continue using solid fuels.
Show more [+] Less [-]Infants' indoor and outdoor residential exposure to benzene and respiratory health in a Spanish cohort
2017
Ferrero, Amparo | Esplugues, Ana | Estarlich, Marisa | Llop, Sabrina | Cases, Amparo | Mantilla, Enrique | Ballester, Ferran | Iñiguez, Carmen
Benzene exposure represents a potential risk for children's health. Apart from being a known carcinogen for humans (group 1 according to IARC), there is scientific evidence suggesting a relationship between benzene exposure and respiratory problems in children. But results are still inconclusive and inconsistent. This study aims to assess the determinants of exposure to indoor and outdoor residential benzene levels and its relationship with respiratory health in infants. Participants were 1-year-old infants (N = 352) from the INMA cohort from Valencia (Spain). Residential benzene exposure levels were measured inside and outside dwellings by means of passive samplers in a 15-day campaign. Persistent cough, low respiratory tract infections and wheezing during the first year of life, and covariates (dwelling traits, lifestyle factors and sociodemographic data) were obtained from parental questionnaires. Multiple Tobit regression and logistic regression models were performed to assess factors associated to residential exposure levels and health associations, respectively. Indoor levels were higher than outdoor ones (1.46 and 0.77 μg/m3, respectively; p < 0.01). A considerable percentage of dwellings, 42% and 21% indoors and outdoors respectively, surpassed the WHO guideline of 1.7 μg/m3 derived from a lifetime risk of leukemia above 1/100 000. Monitoring season, maternal country of birth and parental tobacco consumption were associated with residential benzene exposure (indoor and outdoors). Additionally, indoor levels were associated with mother's age and type of heating, and outdoor levels were linked with zone of residence and distance from industrial areas. After adjustment for confounding factors, no significant associations were found between residential benzene exposure levels and respiratory health in infants. Hence, our study did not support the hypothesis for the benzene exposure effect on respiratory health in children. Even so, it highlights a public health concern related to the personal exposure levels, since a considerable number of children surpassed the abovementioned WHO guideline for benzene exposure.
Show more [+] Less [-]Health burden attributable to ambient PM2.5 in China
2017
Song, Congbo | He, Jianjun | Wu, Lin | Jin, Taosheng | Chen, Xi | Li, Ruipeng | Ren, Peipei | Zhang, Li | Mao, Hongjun
In China, over 1.3 billion people have high health risks associated with exposure to ambient fine particulate matter (PM2.5) that exceeds the World Health Organization (WHO) Air Quality Guidelines (AQG). The PM2.5 mass concentrations from 1382 national air quality monitoring stations in 367 cities, between January 2014 and December 2016, were analyzed to estimate the health burden attributable to ambient PM2.5 across China. The integrated exposure-response model was applied to estimate the relative risks of disease-specific mortality. Disease-specific mortality baselines in province-level administrative units were adjusted by the national mortality baseline to better reveal the spatial inequality of the health burden associated with PM2.5. Our study suggested that PM2.5 in 2015 contributed as much as 40.3% to total stroke deaths, 33.1% to acute lower respiratory infection (ALRI, <5yr) deaths, 26.8% to ischemic heart disease (IHD) deaths, 23.9% to lung cancer (LC) deaths, 18.7% to chronic obstructive pulmonary disease (COPD) deaths, 30.2% to total deaths combining IHD, stroke, COPD, and LC, 15.5% to all cause deaths. The population weighted average (PWA) attributable mortality rates (10−5 y−1) were 112.0 in current year analysis, and 124.3 in 10-year time lag analysis. The Mortality attributable to PM2.5 in 10-year time lag analysis (1.7 million) was 12% higher than the current year analysis (1.5 million). Our study also estimated site-specific annual PM2.5 concentrations in scenarios of achieving WHO interim targets (ITs) and AQG. The mortality benefits will be 24.0%, 44.8%, 70.8%, and 85.2% of the total current mortalities (1.5 million) when the PWA PM2.5 concentrations in China meets the WHO IT-1, IT-2, IT-3, and AQG, respectively. We expect air quality modeling and cost-benefits analysis of emission reduction scenarios and corresponding health benefits in meeting the site-specific annual PM2.5 concentrations (WHO IT-1, IT-2, IT-3, and AQG) this study raised.
Show more [+] Less [-]Heavy metal concentrations in some gastropods and bivalves collected from the fishing zone of South India
2017
Ragi, A.S. | Leena, P.P. | Cheriyan, Eldhose | Nair, S.M.
The present study investigates heavy metal concentrations in gastropods and bivalves collected from major fishing centers in South India. Three gastropods, Bursa spinosa, Tibia curta, and Murex trapa, and two bivalves, Perna viridis and Villoritta cyprinoids, were collected for the analysis of heavy metals. The metals in the present study followed the order Mg>Ca>Zn>Fe>Cu>Mn>Cr>Pb>Ni>Co>Cd. Trace metal concentrations in the soft tissue of the molluscs varied as follows: for Cd: 0.04–5.33, Co: 0.09–0.87, Cr: 2.18–7.59, Cu: 9.54–37.02, Mn: 1.30–8.50, Ni: 0.94–3.21, Pb: 1.16–2.64 and Zn: 68.16–113.64mgkg−1. Metal concentrations in all the species were below the limits proposed by the World Health Organization, except for Pb and Cd. This baseline study suggests that the levels of toxic metals in M. trapa, T. curta, and B. spinosa should be continuously monitored to assess the fate and effects of these metals in this fragile ecosystem.
Show more [+] Less [-]Arsenic and mercury concentrations in marine fish sourced from local fishermen and fish markets in mine-impacted communities in Ratatotok Sub-district, North Sulawesi, Indonesia
2017
Bentley, Keith | Soebandrio, Amin
Mesel gold mine, Ratatotok Sub-district, North Sulawesi, Indonesia deposited about 4.5millionm3 of detoxified tailings containing arsenic (As) and mercury (Hg) via a submarine pipeline into Buyat Bay. As and Hg analysis of 216 fish muscle tissue composites from subsistence fishermen, local markets and a reference market confirmed that mean As levels were comparable between locations (range 1.71 to 2.12mg/kg wet weight (ww)) and <10% of the Australia New Zealand standard. Mean Hg concentrations were highest for the artisanal fishermen group (0.23mg/kg ww), similar between the local markets (0.11–0.14mg/kg ww) and lower at the reference market (0.04mg/kg ww). A 12-month fish availability study identified that the results were due to the different coral and deep ocean species assemblages. All mean values were <50% of the FAO/WHO/Codex standard for Hg. The results confirmed that there was no contamination from the deposited submarine tailings.
Show more [+] Less [-]Spatio-temporal variation and influence factors of PM2.5 concentrations in China from 1998 to 2014
2017
Lu, Debin | Xu, Jianhua | Yang, Dongyang | Zhao, Jianan
Based on the remote sensing retrieval of PM2.5 concentration data in the long-time series, both the linear regression and grey system correlation analysis methods were employed to analyze the spatial and temporal pattern, variation trend and the main influencing factors of PM2.5 concentration in China from 1998 to 2014. The results showed that only 16.21%–24.67% of the land area in China PM2.5 concentrations reached the annual average criterion value of 10 μg/m3 set by the World Health Organization (WHO) in 1998–2014; the PM2.5 concentrations were greater than 95 μg/m3 mainly in Xinjiang Taklimakan Desert, west of Tianjin and the central region of Hebei. PM2.5 concentration was less than 10 μg/m3 mainly in Tibet, western Sichuan, northeastern Yunnan, Taiwan, northern Xinjiang, northern Inner Mongolia and northwest of Heilongjiang. High PM2.5 concentration in the northwest of China was mainly affected by sand and dust, while it was mainly caused by human activities in the eastern region. Except for Taiwan, low PM2.5 concentration areas were mainly located in the economically backward regions. The positive indicators in highly correlation with PM2.5 concentration include the average temperature, the proportion of primary and secondary industry to GDP, industrial consumption, the proportion of fulfilled amount of investment in real estate development to GDP, SO2 emissions and population density. The negative indicators in highly correlation with PM2.5 concentration include the average precipitation, the average wind velocity, the proportion of the tertiary industry to GDP, and the greening coverage rate of the built-up areas.
Show more [+] Less [-]Persistent organochlorine residues in fish and sediments collected from Eastern Aegean coast: Levels, occurrence and ecological risk
2017
Muzyed, Shareef K.I. | Kucuksezgin, Filiz | Tuzmen, Nalan
Organochlorines were determined in fish and sediment collected from Izmir and Çandarlı Bays. The results indicated that ΣCyclodiens were generally predominant contaminants. In all samples, p,p′-DDE was the predominant DDT congener. Aroclors were found in noticeably higher levels than OCPs in sediment and the highest levels of Aroclors, OCPs were found in Nemrut which can be attributed to industrial activities. According to Sediment Quality Guidelines, DDTs were lower than the values that may cause adverse biological risk in sediment samples. Aroclor 1254 in sediments only exceeded the TEL value at Nemrut site. The maximum values of ΣOCPs were found in fish collected from Gülbahçe, while Aroclors were measured in Aliaga. According to related indices, results indicate no recent influxes of DDT in the sampling areas. The estimated daily intake of DDTs, Aroclor1254 were below the acceptable daily intake level recommended by FAO/WHO.
Show more [+] Less [-]Toxic heavy metals in commercially important food fishes collected from Palk Bay, Southeastern India
2017
Arulkumar, Abimannan | Paramasivam, Sadayan | Rajaram, Rajendran
Toxic heavy metals are an important group of emerging chemical contaminants in seafood. Heavy metal concentrations in commercially important and most commonly eaten 10 fish species from Thondi fish landing, southeast coast of India, were determined by atomic absorption spectrometry. The concentrations of heavy metals significantly varied within and between the investigated fish species (P<0.05). The results of this study showed best significant correlations among the toxic heavy metals in the fish samples. It was revealed that Cd, Pb, Cu, and Zn metals were present in the fish samples at various levels. The residual levels of toxic heavy metals were less than the permissible levels specified for human consumption by the European Union, Food and Agriculture Organization and World Health Organization guidelines. Therefore, the fish species found in the Thondi fish landing and their fishery products can be considered safe for human consumption and can be exported worldwide.
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