Assessment of Hazard Index and Incremental Life Cancer Risk Associated with Heavy Metals in the Soils

The purpose of this review was to evaluate the hazard Index and Incremental life cancer risks associated with heavy metal contaminations of the soil for residents in the country. Many scientific articles have been accessible online in the Nigeria were evaluated for the estimation of [Hazard Index and Incremental Life Cancer Risk] for individual heavy metals. The heavy metals considered in this work are; [Lead (Pb), Copper (Cu), Iron (Fe), Manganese (Mn), Zinc (Zn), Chromium (Cr), and Cadmium (Cd)] The concentrations of these metals were obtained from the literature and modeled for, hazard index (HI), and carcinogenic risk (ILCR) via ingestion, inhalation, and dermal pathways for adults following the United State Environmental Protection Agency [USEPA] method. The hazard index for all the exposure pathways (ingestion, inhalation, and dermal contact) was found to be 21914, 1020.7, 580.8, 2.641, 0.272, 0.05165, 0.021, and 0.011[mg/kg/day], for Fe, Mn, Cr, Pb, Cu, Zn, Ni, and Cd respectively. United States EPA considered an overall hazard index value of 1.0 as an acceptable threshold below which no observable clinical effect was reported. In order of magnitude: Fe > Mn > Cr > Pb > Cu > Zn > Ni > Cd, Fe, Mn, and Cr have the highest Hazard Index in all the soil samples analyzed by different researchers in the country. In all the heavy metals reviewed, the Cd has the highest Incremental Life Cancer Risk followed by Cr, Pb, and Ni. This indicated that most of the areas are highly polluted with Cd, Cr, and Pb. Therefore, dwellers of the locations may likely be affected with cancer due to the ingestion, inhalation, and dermal contact with metals. The Overall results suggested that there is probable adverse health effects to an exposed population in all locations reviewed. Therefore, an effort will be made to prevent the transfer of heavy metals in the soil to the surrounding environment should be encouraged and soil remediation to further reduce the concentration of heavy metals needs to be effected immediately at root level.

Environmental Monitoring and Potential Health Risk Assessment from Pymetrozine Exposure among Communities in Typical Rice–Growing Areas of China

Pymetrozine is one of the most common insecticides used in China. This study was conducted to analyse Pymetrozine’s potential exposures through various environmental routes beyond the treatment area. The aim was to estimate the potential health risk for communities due to non-dietary exposure to Pymetrozine in soil and paddy water. Data on registration of pesticides in China, government reports, questionnaires, interviews, literature reviews as well as toxicological health investigations were evaluated to determine the hazard and dose-response characteristics of Pymetrozine. These were based on the US EPA exposure and human health risk assessment methods using exposure from soil and paddy water samples collected between 10 to 20 meters around the resident’s location.The potential exposures from dermal contact through soil and paddy water were estimated. The potential cancer risk from the following routes was evaluated: the ingestion through soil; dermal contact exposure through soil; dermal contact exposure through paddy water; and the potential total cancer risk for residents was less than 1*10− 6. These were within the acceptable risk levels. The potential hazard quotient (HQ) from acute and lifetime exposure by dermal contact through paddy water and soil; acute and lifetime exposure by soil ingestion for residents were less than 1, indicating an acceptable risk level, thus both potential cancer risk and hazard quotient (HQ) were relatively low. Potential human health risk assessment of Pymetrozine in soil and paddy water suggested that negligible cancer risk and non-cancer risk based on ingestion and dermal contact are the main potential routes of exposure to residents.

HEALTH RISK DUE TO HEAVY METAL(LOID)S EXPOSURE THROUGH FINE PARTICULATE MATTER AND SEDIMENTED DUST IN PEOPLE LIVING NEXT TO A BEACH CONTAMINATED BY MINE TAILINGS

The non-carcinogenic hazard index (HI) and the carcinogenic risk index (CRI) due to exposure to metal(loid)s were assessed in children and adults living adjacent to a beach contaminated with mine tailings. Chromium (Cr), nickel (Ni), cadmium (Cd), arsenic (As), zinc (Zn), copper (Cu), lead (Pb) and manganese (Mn) were determined in fine particulate matter (PM2.5) and sedimented dust (SD) in school and residential microenvironments. The HI in children was 13.8, 8.1, 5.4, 2.4, 2.3 and 1.8-times greater than the safety threshold (1.0) for Cr, As, Pb, Mn, Cu, and Cd, respectively; 84.1 % explained by dermal contact and 10.9 % by ingestion of SD. The CRI for Cr and As was 3.7 and 3.2 times above the acceptable risk (> 1 × 10–4), explained by the inhalation of PM2.5 and SD, respectively. In adults, the CRI for As and Cr was 46.0 and 2.8 times greater than 1 × 10–4; As risk is explained by dermal contact and inhalation of SD, and Cr by inhalation of PM2.5. This study reports a high risk of potential adverse health effects on children and adults due to exposure to these elements present in the particles and dust studied.

Anthropogenic Nitrate Pollution in Groundwater and Its Health Risks in The View of Background Concentration in a Semi-Arid Area of Rajasthan

An increased nitrate (NO3-) concentration in groundwater has been a rising issue on a global scale in recent years. Through different consumption mechanisms, it clearly illustrates the adverse effects on human health. The goal of this present study is to assess the natural and anthropogenic NO3- concentration in groundwater and its related risks to human health in the different groups of ages such as children, males, and females. Groundwater samples (n=101) were obtained and analysed for their physicochemical components, along with the nitrate concentration in a semi-arid area of Rajasthan. The results show that most of the samples were influenced by anthropogenic activities. The background and anthropogenic levels had been estimated and marked as 7.2 mg/L and 13.3 mg/L for the background and anthropogenic concentrations, respectively. About 83% of nitrate samples were exceeded the background limit, while 28% of the samples were beyond the permissible limit of 45 mg/L as stated by the Bureau of Indian Standards (BIS). Nitrate health risks were also measured by oral intake and dermal contact sources for the residents in this area. The oral exposure of nitrate was very high as compare to dermal contact. With regards to the non-carcinogenic health risk, the total Heath Index (HITotal) values of groundwater nitrate in the study area varied from 0.045 to 3.153 with an average of 0.964 for males, 0.053 to 3.726 with an average of 1.139 for females, and 0.061 to 4.278 with an average of 1.308 for children. The nitrate health risk assessment shows that about 38%, 46%, and 49% of groundwater samples constitute the non-carcinogenic health risk to males, females, and children, respectively.

Concentration and risk assessment of toxic metals in indoor dust in selected schools in Southeast, Nigeria

The health risk of students’ exposure to some potentially toxic metals in classroom dusts in Southeast, Nigeria was assessed. Dust particles were collected from classrooms in some public high schools and digested with aqua regia before analysis for selected metals by atomic absorption spectrophotometry. The geoaccumulation index, contamination factor and the pollution load index were assessed from the metal concentrations of the dust. Hazard quotient and cancer risk index were used to estimate the potential health risk of students’ exposure to the metals in the dust. The metal concentrations (mg/kg) were in the ranges of 1.57–175.38 (Cr); 0.93–463.28 (Cu); 31.94.76–6623.41 (Fe); 4.96–143.98 (Ni); 2.64–375.27 (Zn); and 2.35–53.96 (Pb).The geo-accumulation index values showed that all the dust samples were polluted with Fe and Cr; and unpolluted with other metals with few exemptions. The contamination factor values showed that all the schools but one had a low contamination status due to Ni and Cu. There was moderate contamination by Pb at all the schools but two. All the schools had high contamination of Cr and Fe. The pollution load index indicated that the quality of all the classrooms was deteriorated. The calculated values of hazard quotient indicated that ingestion of dust at most of the classrooms would have no significant risk of non-carcinogenic effects on the health of the students. Dermal contact with the dust at all the classrooms would expose students to adverse effects of Fe. There will be adverse effect due to Pb for dermal contact with dust at most of the schools. Ingestion of dust particles at classrooms in all the schools would have carcinogenic effect due to Ni. Correlation analysis indicated that the sources of the metals varied. This study provided baseline data for relevant bodies to use in monitoring and controlling pollution so as to protect students from toxic metals.

Imaging mass spectrometry : a new way to distinguish dermal contact from administration of cocaine, using a single fingerprint

Here we show a new and significant application area for mass spectrometry imaging. The potential use of for fingerprints to determine reveal drug use has been widely reported, with potential...

Cholinesterase Inhibition and Exposure to Organophosphate Esters in Aircraft Maintenance Workers

INTRODUCTION: Aircraft maintenance workers may be exposed to organophosphates in hydraulic fluid and engine oil. Previous research has indicated that inhalation may not be the primary exposure route. This study sought to measure dermal contact and inhalation in conjunction with cholinesterase inhibition and determine if Air Force Specialty Code serves as an exposure predictor.METHODS: Aircraft maintenance workers were sampled for changes in acetylcholinesterase and butyrylcholinesterase. Dermal contact was measured using wrist-worn silicone passive dosimeters and inhalation exposure was measured using thermal desorption tube air sampling.RESULTS: Overall prevalence of any cholinesterase inhibition in the study population was 25.33%. Prevalence of inhibition of acetylcholinesterase and butyrylcholinesterase was 18.67% and 6.67%, respectively. The mean tributyl phosphate result was 1.71 ng of tributyl phosphate per gram of wristband (ng g1) [95% confidence interval (CI): 5.63, 9.05]. Triphenyl phosphate was more prevalent, with only one sample below the limit of detection (mean 1386.26 ng g1; 95% CI: 7297.78, 10,070.31), and tricresyl phosphate was found in every sample (mean 4311.65 ng g1; 95% CI: 8890.24, 17,512.31). No organophosphates were detected via air sampling.DISCUSSION: Workers experienced organophosphate exposure and cholinesterase inhibition, but the study was not large enough to establish a statistically significant association between exposure and disease. Exposure to organophosphate esters is more likely to occur through contact and absorption of chemicals through the skin than through inhalation of oil mists. Air Force Specialty Code does not appear to be a good predictor of exposure to organophosphates. Future studies should consider using a larger sample size.Hardos JE, Rubenstein M, Pfahler S, Sleight T. Cholinesterase inhibition and exposure to organophosphate esters in aircraft maintenance workers. Aerosp Med Hum Perform. 2020; 91(9):710714.

Health Risk Assessment in Agricultural Soil Potentially Contaminated by Geogenic Thallium: Influence of Plant Species on Metal Mobility in Soil-Plant System

In agricultural soils, thallium (Tl) of geogenic origin may represent a potential risk for human health, mainly via ingestion of food crops. In this work, a pot experiment was carried out to evaluate (1) the bioavailability of Tl and other potentially toxic elements (PTEs) in an agricultural soil with naturally occurring Tl; (2) the uptake and accumulation of PTEs in Lactuca sativa L. var. acephala, Diplotaxis tenuifolia L. DC and Silene latifolia Poir; (3) the health risks arising from plant and soil ingestion by different subpopulations and dermal contact of soil by farmers. In soil, only Tl and Pb pseudototal contents were above Italian screening values. Nevertheless, the promptly bioavailable contents of all PTEs were always below internationally recognized trigger values. Plants affected PTE bioavailability in soil by their rhizodepositions and accumulated PTEs in their shoots. Acceptable risks (hazard index < 1) arose from dietary intake of both L. sativa L., D. tenuifolia L. and dermal contact of soil by farmers. Significant health risks can derive from the intake of S. latifolia Poir. (accumulating high Tl concentrations), in particular by children (HI = 74). In conclusion, an adequate management and crop selection are needed to profitably exploit soils with geogenic Tl for agricultural purposes.

Selected Metals in Urban Road Dust: Upper and Lower Silesia Case Study

In this study, urban road dust (URD) samples were collected in two populated agglomerations of Wrocław and Katowice (Lower and Upper Silesia) in Poland. Both the total concentrations of URD-bound Mn, Ni, Cu, Zn, As, Rb, Ba, Cr, Mg, and Al and concentrations of their water-soluble fraction were determined. The contamination characteristics and health risk related to these elements were assessed. Contamination level assessment was done by Pollution Load Index (PLI), which indicated much higher pollution of Katowice agglomeration than Wrocław. The enrichment factor values (EF) showed that the most elements in both Katowice and Wrocław orginated from anthropogenic sources. The calculations of geo-accumulation index (Igeo) showed that Zn and As are the key pollutants in Katowice; and in the Wrocław region, Cu, Zn, Cr, and Ni are. The principle component analysis (PCA) and correlation analysis provide information about the potential sources of metals. Additionally, a positive matrix factorization (PMF) was performed and four factors in PMF analysis were found and then interpreted by comparing to the source profiles. Three contamination sources were revealed: fossil fuel combustion, road traffic and industrial emissions. Although the main source of studied metals in Lower Silesia is road traffic, in Upper Silesia, domestic heating with the use of hard and brawn coal and industrial activity predominates. Human exposure to individual toxic metals through road dust was assessed for both children and adults. By calculating the average daily dose (ADD) via ingestion, inhalation, and dermal contact, it was found that ingestion and then dermal contact were the greatest exposure pathways for humans in Katowice and Wrocław. Children had greater health risks than adults. According to the health risk assessment, the overall non-carcinogenic risks in both urban areas was rather low. The only exception was As bound to urban road dust in Katowice agglomeration, which indicates risk for children when ingested. The total excess cancer risk (ECR) was also lower than the acceptable level (10−6–10−4) for both adults and children, although ECR for Katowice was closer to this limit.