Risk assessment of human exposure to potentially toxic metals in indoor dust from some small and medium scale enterprise workplace environments in southern Nigeria

Abstract

This study concerns an assessment of indoor dust from printing press, car spray painting and metal design workshops, with the aim of evaluating the occupational risk arising from exposure to metals present in the dust. The levels of Cd, Pb, Cr, Ni, Cu, Co, Mn, Zn and Fe in the dust samples were quantified by means of atomic absorption spectrometry. The concentrations of metals (mg kg−1) in the indoor dust from these workplace environments varied from <0.003–208 for Cd, 26.5–1530 for Pb, 7.80–346 for Cr, 10.5–490 for Ni, 32.0–1915 for Cu, 3.50–232 for Co, 169–20,300 for Zn, 87.5–7260 for Mn and 8900–661,000 for Fe. The hazard index values were above one for different age groups except for the exposure of teenagers and adults to metals in dusts in the printing press studios and car spray painting workshops. The carcinogenic risk for all age groups relating to human contact with metals (Cd, Pb, Cr and Ni) in dust from these workplace environments via three exposure pathways: oral ingestion, inhalation and dermal contact, were above the safe level of 1.0 × 10−6 but not up to the level (1.0 × 10−4) that requires remedial action.

Determination of heavy metals and health risk assessment in indoor dust from different functional areas in Neyshabur, Iran

“…As can be seen, in the cold season, the highest mean EnFs in the high traffic area belong to Pb> Cd> Zn> Cu> Ni> Cr> Mn> Co in that order, and for the low traffic area and the rural area, this order changes to Cd> Zn> Pb> 55 The EnF values of Mn, Co and Cr were less than 10, indicating that they are from natural sources rather than human activities. In indoor dust, the EnF values of lead , cadmium , zinc , copper (7.6-51) and nickel (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32) were all greater than 10, suggesting that they have been enriched to varying degrees by artificial sources and factors such as toys, paints, appliances, heating, cooking and smoking. 56 The EnF values obtained for different traffic areas follow a clear trend, in the sense that as traffic decreases so does EnF.…”

“…Lead and zinc are the two main pollutants released from brazing rods, the exhaust of vehicles and brake lines (engines release 75% of gasoline's lead content into the air). 16 There are also notable amounts of zinc in tires, oils and especially guardrails. Brakes are also an important source of copper.…”

Occurrence and exposure risk of mono-aromatic hydrocarbons in selected petroleum product jetty impacted soils from the Niger Delta, Nigeria

“…The parameters in equation 2-10 are defined in the supplementary material (Table 1 and 2) and Table 1 as described in USEPA, [15,16]; Iwegbue et al [17].…”

Implementing an emissions-rate model in computational fluid dynamics simulations of contaminant diffusion processes: A case study with xylene in painting workshops

“…Both experimental 7–12 and computational fluid dynamics (CFD) simulations 13–16 have been frequently used to investigate the air quality of residential areas. Several researchers 17–19 have focused on the air distribution of workshops. The pollution species and diffusion processes involved in manufacturing departments are complex, especially in secondary industries.…”

“…The pollution species and diffusion processes involved in manufacturing departments are complex, especially in secondary industries. There have, therefore, been many reports 17,18 of workshop contamination, indicating that numerous volatile organic compounds (VOCs) were identified in the air, including acetate, toluene and xylene. 19 These chemicals can cause severe neuroses and heart diseases.…”