Abstract

Background: Nigeria has a growing spray painting industry being a nation with one of the highest number of automobiles in Africa. _ENREF_1Spray painters work mainly in the small and medium scale sectors of the Nigerian economy; it is a vocation characterized by exposure to chemical hazards especially aerosolized organic solvents in the form of volatile organic compounds (VOCs). The adverse health effects of organic solvents are majorly respiratory, neurotoxic and dermatologic. The burden of health problems related to organic solvents exposure among spray painters in Nigeria remains under-studied. The study objectives were to identify common organic solvents in use by painters, assess knowledge of occupational hazards among painters, workshop safety and sanitation, quantify solvent exposures, describe common health problems, assess lung functions of painters and controls and the relationship between solvent exposure and health problems of painters as well as controls.
Methods:A comparative cross sectional study design was employed to survey 120 spray painters and 120 controls (electronic technicians) in Ife Central and Ife East local government areas of Osun State, Nigeria. A semi-structured interviewer administered questionnaire was used to obtain data on socio-demographic characteristics, work patterns, common paints and paint-products in use and health symptoms of the respondents. Inhalation exposure index using the Fidler’s method was derived from spray painters’ work exposure history. Clinical examination, lung function and serum bile acids assay of respondents were conducted. In addition, a checklist was used to survey the spray painting workshops. Total VOC levels were determined in 37 spray painting and 31 electronic workshops. Data were analysed using SPSS version 20 and statistical significance was set at p<0.05
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Results:N-butyl acetate (25-50%), ethanol (50-100%) and n-butyl acetate(20-35%)were the most common organic solvents(as derived from the material safety data sheets of the products) in paints, thinners and lacquersrespectively that painters used commonly in Ile-Ife. Windows were available in only 5 (13.5%) spray painting workshops and 23 (62%) workshops had retractable tarpaulin at the entrance, while fire extinguishers and first aid kits were not available in any workshop. Majority (69.2%) of spray painters had good knowledge about PPE while 79(65.8%) painters had poor knowledge about organic solvent-related occupational hazards.
The 8-hour time-weighted average concentration of total VOC in spray painting workshops was 13.4ppm which is above the national permissible exposure limits of 1.9ppm. Total serum bile acids (a biomarker of solvent exposure) was significantly elevated in painters (8.7±3.4mmol/l) than controls (4.7 ±2.2 mmol/l) (t=10.4, df=213, p<0.05). Only 9 (7.5%) spray painters perceived their use of PPE as adequate. One hundred and seven spray painters (89.2%) noticed paint in sputum immediately after painting. Excessive eye-tear, recurrent cough, chest wheeze, short term memory loss and chest pain were significantly more common in spray painters than controls (p<0.05). Clinically, keratitis and dry skin was more common in painters than controls. (p<0.05) Forced vital capacity % predicted (FVC % predicted) was significantly lower in spray painters (93.9 ±10.8%) than controls (96.7± 8.2) (t = -2.3, df=238 p< 0.001). The forced expiratory volume % predicted in the first second (FEV1% predicted) was lower in spray painters (94.6±12.2) than controls (100.3±9.1) (t=-4.058, df=238, p=0.002). FEV1/FVC% was significantly lower among spray painters (85.5±8.7%) as compared with controls (87.9±6.2) (t=-2.9 df=238, p= 0.005). Painters with high exposure index significantly had visual impairment and immediate recall deficit. (p<0.05).
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Conclusion: Organic solvent exposure was higher among spray painters than controls. This high exposure levels had adverse effects on the health of spray painters and lung function test results were lower in painters than controls. More needs to be done as regards workplace regulation and enforcements to ensure that spray painters comply with minimum standards of occupational safety, workplace hygiene and sanitation.