Vehicle-Derived Heavy Metals and Human Health Risk Assessment of Exposure to Communities along Mubi-Yola Highway in Adamawa State (Nigeria)

Abstract

In this study, the health risk caused by heavy metals exposure to communities along Mubi-Yola highways was evaluated. Samples from Mubi, Hong, Gombi, Song, and Gerei were collected and analyzed for Lead (Pb), Cadmium (Cd), Chromium (Cr), Zinc (Zn), Cupper (Cu), and Nickel (Ni) using Atomic Absorption Spectrophotometer (AAS). The mean concentrations of the metals used for the risk assessment were observed to fall in this order Zn>Pb>Ni>Cu>Cd>Cr. The noncarcinogenic risk based on the target hazard quotient (THQ) and human health index (HI) values for each exposure pathway and for each metal were observed to be less than (<) 1 which means, exposure to the heavy metals has no immediate risks for both the adults and children in the settlements. The lifetime cancer risk (CRI) for the metals for both the ingestion (CRI Ing ) and inhalation (CRI Inh ) exposure pathways were observed to pose no lifetime carcinogenic risk. The CRI for all the exposure pathways and for all age categories were <10 -4. Similarly, the combine Bwatanglang et al.; JSRR, 23(1): 1-13, 2019; Article no.JSRR.48137 2 effect or total cancer risk (TCRI) for each exposure pathway show high probability for carcinogenic risk by ingestion route compared to exposure by inhalation. The order of exposure were observed to be adults<children. Though the CRI and TCRI results were observed to be within the acceptable range for developing cancer, the result however suggest that children could be more susceptible to potential carcinogenic risk following continual exposure to heavy metals from vehicular activity. Indicating some concern about the expansion of unregulated settlements along heavy traffic highways. Original Research Article

Risk of exposure to metals in soil contaminated by steel industry waste for a population in Volta Redonda, RJ

“…The potential carcinogenic and non-carcinogenic risks that may arise from the exposure of adults and children living in the study area to metals in the soil were determined by combining exposure pathways. These risk pathways involve acceptable daily intake (ADI) of metals (mg Kg -1 ) through ingestion (Ing), inhalation (Inal), or dermal exposure (Derm) using the methods described in Equations 1 to 3 (Lange, 2018;Bwatanglang et al, 2019).…”

“…The cancer risk index (CRI) represents the likelihood of an individual developing any cancer throughout his or her lifetime and is calculated by combining ADI with each contaminant (c) cancer slope factor (CSF). Equation 6describes such an index (Lange, 2018;Bwatanglang et al, 2019).…”

“…In turn, HQ or HI > 1 raise genuine concern. CRI is considered negligible if < 10 -6 , acceptable or tolerable if 10 -6 < CRI < 10 -4 , and high if > 10 -4 (Lange, 2018;Bwatanglang et al, 2019).…”

“…The exposure factors used in this study are based on the study carried out by Gabarrón et al (2017). The hazard quotient (HQ) was used to analyze the potential non-carcinogenic effect of metals in soil samples, relating ADI with its reference dose (RfD) (Table 2) for each exposure and contaminant pathway (c), as described in Equation 4 (Lange, 2018;Bwatanglang et al, 2019).…”

“…HQ = ADI c /RfD c (4) As described in Equation 5, the health index (HI) for various contaminants, expressed as HQ sum for each contaminant (c), describes the non-carcinogenic cumulative effect of their combination in soil samples (Lange, 2018;Bwatanglang et al, 2019).…”