Health risk assessment of lead, cadmium, heavy metals and metalloids in residential paint flakes from indoor wall surfaces

Abstract

Paint components pose risky metals like lead, cadmium, arsenic, and mercury that endanger occupants, mainly children and pregnant women. To assess the levels and health risks of 14 metals in paint flakes from indoor walls of residential houses in four states in South-western Nigeria. Flaked paints were collected from 144 houses where children reside. Metals were analysed using an inductively coupled plasma-optical emission spectrometer. The cadmium (Cd), lead (Pb), arsenic (As), and chromium (Cr) levels (mg/kg) ranged from 1239.9 to 2254.2, 1126.5 to 3080.3, 822.1 to 1492.0, and 2.5 to 60.6 in all the state capitals examined, respectively. All samples examined in this study were above the regulated permissible limits. The US Environmental Protection Agency estimated health risk assessment model was used to calculate the chronic daily intake, hazard quotient, hazard index (HI), and lifetime cancer risk (LCR). HI > 1 was highest in the ingestion route (2.592341: adults, 24.5153: children), and the LCR in children and adults followed the order of LCRingestion > LCRinhalation > LCRdermal. The probability of developing cancer over a lifetime, Total Lifetime Cancer Risk, for children exceeded the limit range for Pb, Mn, and Zn in the paint flakes from all the buildings, while almost all buildings where children resided exceeded the limit range for Cd. The study revealed that paint flakes from indoor walls pose a significant source of metal contamination and health risk, especially for children. In Nigeria, there is a need for stricter regulation and monitoring of metal content in paints and paint flakes.

Keywords: Health implications; Heavy metals; Indoor exposure; Leaded paints; Nigeria.