56 research outputs found
Source Identification of Chemical Contaminants in Environmental Media of a Rural Settlement
Principal Component Analysis (PCA) was used to identify the source of contaminants in Ubeji
settlement. The contaminants assessed are oil and grease, TPH and related heavy metals (Cd, Cr, Cu,
Ni, Pb and Zn). A total of 48 groundwater, 100 surface water, 160 soil and 100 sediment samples were
collected from the study site from March to August, 2011. Measurements of oil and grease and TPH in
samples were done gravimetrically, while atomic absorption spectrophotometry was used for
determination of heavy metals. The results show significant contamination, as TPH levels in
groundwater and surface water range from 22 to 96 mg L-1, while soil and sediment levels range from
600 to 2300 mg kg-1. Also, Cd, Cr and Pb levels in the groundwater and surface water range from 0.02
to 0.47, 0.51 to 1.3 and 1.7 to 4.1 mg L-1, respectively while soil and sediment levels range from 0.04
to 0.48, 28 to 66, 45 to 69 mg kg-1, respectively. However, Cu, Ni and Zn are within safe limits. PCA
revealed that the source of the contaminants is a refinery and petrochemical company located close to
the settlement
Health Risk Assessment of Exposure to Metals in a Nigerian Water Supply
This article reports the health risk associated with chronic intake of metals in the municipal water supplies
of Eleyele and neighboring towns in the Ibadan metropolitan area of Nigeria. A total of 42 composite
samples, consisting of treated water from the water treatment facility and residential areas receiving
personal-use water (i.e., tap water) directly from the facility, as well as raw water from the treatment
facility's water supply dam were sampled twice every month for 7 months. Concentrations of the metals
were determined by atomic absorption spectrophotometry. Among the metals studied, Cd, Co, Cr, and Pb
were detected at concentrations higher than maximum regulatory limits. Cd, Co, Cr, and Pb
concentrations in treated water at the treatment facility ranged from 0.08–0.10, 0.14–0.16, 0.04–0.22 and
0.07–0.36 mg L , respectively, while personal-use water ranged from 0.08–0.11, 0.15–0.29, 0.02–0.29, and
0.12–0.65 mg L , respectively. Likewise, concentrations of the metals at the dam ranged from 0.06–0.08,
0.17–0.20, 0.13–0.37, and 0.03–0.15 mg L , respectively. It is estimated that exposure to the metals in the
water supply results in oncological and non-oncological systemic health risks higher than is generally
acceptable for drinking water
Prioritizing hazardous pollutants in two Nigerian water supply schemes: a risk-based approach
Objective To rank pollutants in two Nigerian water supply schemes according to their effect on human health using a risk-based approach.
Methods Hazardous pollutants in drinking-water in the study area were identified from a literature search and selected pollutants were monitored from April 2010 to December 2011 in catchments, treatment works and consumer taps. The disease burden due to each pollutant was estimated in disability-adjusted life years (DALYs) using data on the pollutant’s concentration, exposure to the pollutant, the severity of its health effects and the consumer population.
Findings The pollutants identified were microbial organisms, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead and zinc. All were detected in the catchments but only cadmium, cobalt, chromium, manganese and lead exceeded World Health Organization (WHO) guideline values after water treatment. Post-treatment contamination was observed. The estimated disease burden was greatest for chromium in both schemes, followed in decreasing order by cadmium, lead, manganese and cobalt. The total disease burden of all pollutants in the two schemes was 46 000 and 9500 DALYs per year or 0.14 and 0.088 DALYs per person per year, respectively, much higher than the WHO reference level of 1 × 10−6 DALYs per person per year. For each metal, the disease burden exceeded the reference level and was comparable with that due to microbial contamination reported elsewhere in Africa.
Conclusion The estimated disease burden of metal contamination of two Nigerian water supply systems was high. It could best be reduced by protection of water catchment and pretreatment by electrocoagulation
The burden of disease attributable to ambient PM2.5-bound PAHs exposure in Nagpur, India
Polycyclic aromatic hydrocarbons (PAHs) bound to PM2.5 are
genotoxic carcinogens that can also elicit non-cancer effects. Previous
studies report substantial burdens of PAHs-related lung cancer, but no
estimate for other cancer types or non-carcinogenic burden. Here, we
assessed the burden of disease, in DALYs/person/year, attributable to
thirteen priority PAHs in PM2.5 in Nagpur district, for several endpoints
linked to benzo[a]pyrene, to inform policy decision-making for
mitigation. We conducted detailed assessment of concentrations of PAHs in
nine areas, covering urban, peri-urban and rural environments, from
February 2013 to June 2014. PAHs concentrations were converted to
benzo[a]pyrene equivalent concentration for cancer and non-cancer effects
using relative potency factors and relative toxicity factors derived from
quantitative structure-activity relationships, respectively. We derived
severity for each endpoint using GBD 2016 dataset. The annual average
concentration of total PAHs in Nagpur district was 458±246 ng/m3, and
results in 0.011 DALYs/person/year (49,000 DALYs/year), much higher than
the WHO reference limit of 1×10-6 DALYs/person/year. PAHs-related burden
follow this order: developmental (mostly cardiovascular) impairment
(55.1%) > cancer (26.5%) or lung cancer (23.1%) > immunological
impairment (18.0%) > reproductive abnormally (0.4%). The estimated
DALYs/person/year is high. Mitigation intervention should target
combustion sources having the highest level of exposure
Systemic chronic health risk assessment of residential exposure to Cd2+and Cr6+in groundwater
A health risk assessment was undertaken for residents of Ubeji community who
consume groundwater contaminated with trace metals. A total of 96 composite
groundwater samples were collected in the dry and wet seasons from 12 locally dug
wells, which are major sources of groundwater to the community. Concentrations of the
metals were determined by atomic absorption spectrophotometry and were found to
vary with season. Among the metals studied, Cd , Cr , and Pb were detected at
concentrations higher than maximum regulatory limits. Cd concentrations (mg L )
range from 0.03 to 0.06 and 0.02 to 0.05 in the dry and wet seasons, respectively, while
Cr levels (mg L ) range from 0.59 to 0.67 and 0.34 to 0.53, respectively, for the two
seasons. Also, Pb levels (mg L ) range from 2.8 to 3.4 and 2.7 to 3.1 in the dry and
wet seasons, respectively. It is estimated that exposure to metals in the community
drinking water results in carcinogenic and non-carcinogenic risks that are higher than
the generally acceptable risks of drinking water. Therefore, the results indicate that the
concentrations of the metals in the groundwater are high and the consumption of water
from the community wells may result in systemic chronic health risk to the residents
The health burden and economic costs averted by ambient PM 2.5 pollution reductions in Nagpur, India
National estimates of the health and economic burdens of exposure to ambient fine particulate matter (PM2.5) in
India reveal substantial impacts. This information, often lacking at the local level, can justify and drive mitigation
interventions. Here, we assess the health and economic gains resulting from attainment of WHO guidelines for
PM2.5 concentrations – including interim target 2 (IT-2), interim target 3 (IT-3), and theWHO air quality guideline
(AQG) – in Nagpur district to inform policy decision making for mitigation. We conducted a detailed assessment
of concentrations of PM2.5 in 9 areas, covering urban, peri-urban and rural environments, from February
2013 to June 2014. We used a combination of hazard and survival analyses based on the life table method to calculate
attributed annual number of premature deaths and disability-adjusted life years (DALYs) for five health
outcomes linked to PM2.5 exposure: acute lower respiratory infection for children b5 years, ischemic heart disease,
chronic obstructive pulmonary disease, stroke and lung cancer in adults !25 years. We used GBD 2013
data on deaths and DALYs for these diseases. We calculated averted deaths, DALYs and economic loss resulting
from planned reductions in average PM2.5 concentration from current level to IT-2, IT-3 and AQG by the years
2023, 2033 and 2043, respectively. The economic cost for premature mortality was estimated as the product of
attributed deaths and value of statistical life for India, while morbidity was assumed to be 10% of the mortality
cost. The annual average PM2.5 concentration in Nagpur district is 34± 17 μg m−3 and results in 3.3 (95% confidence
interval [CI]: 2.6, 4.2) thousand premature deaths and 91 (95% CI: 68, 116) thousand DALYs in 2013 with
economic loss of USD 2.2 (95% CI: 1.7, 2.8) billion in that year. It is estimated that interventions that achieve IT-2,
IT-3 and AQG by 2023, 2033 and 2043,would avert, respectively, 15, 30 and 36%, of the attributed health and economic
loss in those years, translating into an impressively large health and economic gain. To achieve this, we
recommend an exposure-integrated source reduction approach
Can the Indian national ambient air quality standard protect against the hazardous constituents of PM2.5?
Globally, exposure to ambient fine particulate matter (PM2.5) pollution claims ~9 million lives, yearly, and a
quarter of this deaths occurs in India. Regulation of PM2.5 pollution in India is based on compliance with its
National Ambient Air Quality Standard (NAAQS) of 40 μg/m3
, which is eight times the revised global air quality
guideline (AQG) of 5 μg/m3.But, whether the NAAQS provides adequate protection against the hazardous components in PM2.5 is still not clear. Here, we examined the risk to health associated with exposure to PM2.5–bound polychlorinated biphenyls (PCB), heavy metals and polycyclic aromatic hydrocarbons (PAHs) in an Indian district averaging below the NAAQS. The annual average concentrations of PM2.5 mass, Σ28PCB and Σ13PAHs were 34 ± 17 μg/m3, 21 ± 12 ng/m3 and 458 ± 246 ng/m3, respectively. Concentrations of As, Cr, Mn and Ni in PM2.5 surpassed the screening levels for residential air. Substantial level of risks to health were
associated with exposure to dioxin-like PCBs (Σ12dlPCB), PAHs, As, Cr and Ni. The hazard index or lifetime
cancer risk were 240, or 9 cases per 1000 population, respectively. The estimated risks to health through
exposure to hazardous components, except Ni, were greatest in rural areas, having a lower average PM2.5 con�centration, than urban or peri-urban areas, suggesting higher toxicity potential of rural combustion sources. The large disparity between the estimated risk values and the acceptable risk level suggests that it would take a more stringent standard, such as the global AQG, to protect vulnerable populations in India from hazardous compo�nents in PM2.
Prioritizing hazardous pollutants in two Nigerian water supply schemes: a risk-based approach
Objective
To rank pollutants in two Nigerian water supply schemes according to their effect on human health using a risk-based approach.
Methods
Hazardous pollutants in drinking-water in the study area were identified from a literature search and selected pollutants were monitored from April 2010 to December 2011 in catchments, treatment works and consumer taps. The disease burden due to each pollutant was estimated in disability-adjusted life years (DALYs) using data on the pollutant's concentration, exposure to the pollutant, the severity of its health effects and the consumer population.
Findings
The pollutants identified were microbial organisms, cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead and zinc. All were detected in the catchments but only cadmium, cobalt, chromium, manganese and lead exceeded World Health Organization (WHO) guideline values after water treatment. Post-treatment contamination was observed. The estimated disease burden was greatest for chromium in both schemes, followed in decreasing order by cadmium, lead, manganese and cobalt. The total disease burden of all pollutants in the two schemes was 46 000 and 9500 DALYs per year or 0.14 and 0.088 DALYs per person per year, respectively, much higher than the WHO reference level of 1 × 10−6 DALYs per person per year. For each metal, the disease burden exceeded the reference level and was comparable with that due to microbial contamination reported elsewhere in Africa.
Conclusion
The estimated disease burden of metal contamination of two Nigerian water supply systems was high. It could best be reduced by protection of water catchment and pretreatment by electrocoagulation
Influence of occupational physical activity on anthropometric profile and body composition of bricklayers in Kwara state, Nigeria
ObjectivesOptimal amount of muscle and fat mass has been associated with level of physical activity and are basic determinants of individuals’ health, fitness including occupational performance. The study determined the level of occupational physical activity and influence on anthropometrics, body composition and health of bricklayers in Kwara state, Nigeria.MethodsDescriptive correlational design was used. During the study only three bricklaying sites were functional and all the 45 bricklayers who met the inclusion criteria were purposively selected. Standardized instruments: non-elastic anthropometric tape rule, stadiometre and weight scale were used for anthropometric and body composition measurement while Occupational Physical Activity Questionnaire (OPAQ; r = .72) was used to assess work-related physical activity. Pilot test was conducted to confirm calibration and functionality of body composition equipment. Informed consent was sought from the participants with ethical approval obtained from the Institutional board. Statistical analysis was performed using SPSS V20.0 with descriptive statistics of mean and standard deviation for analyses of body composition and physical activity while inferential statistics of PPMC and t-test were for analysis of hypotheses at a 0.05 alpha level.ResultsParticipants performed vigorous intensity occupational physical activity expending an average of 2,699.1 MET-min∙wk-1. Occupational physical activity negatively correlated with their body mass index (N = 45, r = -.06, r2 = .36%, p = .05); Waist circumference (N = 45, r = -.083, r2 = .69%, p = .05) and positively correlated with their bicep circumference (N = 45, r = .61, r2 = 37.2%, p = .001) and chest circumference (N = 45, r = .40, r2 = 16%, p = .007).ConclusionsBricklaying positively influenced body parameters which might induce health and fitness benefits. However, there is need for health promotion intervention for enlightenment and healthy life-style practice among bricklayers to improve overall health and fitness
Chronic Exposure to Heavy Metals in Public Water Supply and Human Health Risk Assessment
Historic disasters resulting from heavy metals contamination of drinking water emphasize the need to assess the quality of public water
supplies. Currently, millions of people in and around Bangladesh are facing chronic health risk of arsenic poisoning via drinking water.
Therefore, to prevent the re-occurrence of such tragic episodes, heavy metal levels in public water supplies at Agodi-residential area of
Ibadan, Nigeria were determined and human health risk assessment was done for metals whose levels were higher than the US EPA
maximum contaminants level for drinking purpose. Sampling was spread from January to July, 2010 to account for variations in rainy and
dry seasons. 10 public taps were sampled at 5 different times, making a total of 50 water samples collected. Metals concentrations were
determined by atomic absorption spectrophotometry. The mean concentrations (mg L-1) of Cd, Co, Cr+6, Mn and Pb in the sampled water
were 0.05 ± 0.02, 0.14 ± 0.02, 0.21 ± 0.07, 0.17 ± 0.02 and 0.05 ± 0.04, respectively. These values are significantly higher than the US
EPA maximum contaminants level in drinking water. Health risk assessment conducted for adult and child residents, via oral and dermal
routes of exposure, gave overall hazard index values of 19 and 45, respectively, while the estimated cancer risks values were 2E-03 and
9E-04, respectively. These values significantly exceed the target non-cancer hazard index of 1 and target cancer risk of 1E-06. Hence, the
concentrations of the investigating metals in this public water supply are high enough to cause carcinogenic and non-carcinogenic
systemic health effects to adults and children
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