Occupational burden of organic solvent in neurologic disorder

Introduction:   Industrial chemicals have been increased at worksite and significant part of them has human neurotoxicity. Especially organic solvents are well known for the cause of acute and chronic neurological disorder. Health effect of organic solvent is various from pre-clinical symptom and sign to overt disease. The purpose of this study is estimation of the self-reported neurotoxic health outcome due to organic solvent exposure in Korean employed population in 2010.        

Methods:  The prevalence of organic solvents were estimated based on two resources. One was from the results of Korean Working Condition Survey (KWCS) conducted in 2010 as household survey for employed workers. Another one was from Working Environment Survey of Korea (WESK) in 2009 which was conducted as company survey focusing on manufacturing industry. Relative risk (RR) and odds ratio (OR) of neurotoxic symptoms and some neurological disorder due to organic solvents were reviewed from previous peer reviewed articles. Population attributable risk fraction (PAF) was estimated using Levin’s formula. The prevalence of self reported neurological disorder from the KWCS was compared with the PAF.    

Results:  According to KWCS and KWCS, the exposure prevalence of organic solvents was 2.8 % of employed workers. RR and OR of neurotoxic symptoms from previous articles were 1.03 ~ 2.72. The PAF of neurotoxic symptoms were 0.08 ~ 4.5%. In the symptom survey of KWCS, the prevalence of depressive disorder, sleep disturbance which was reported from solvent exposed workers and regarded as work-related, was 2.2% and 4.4% respectively.    

Discussion: Because the most common health effect of organic solvent is nonspecific and transient subjective symptom, the estimation of occupational burden of organic solvents is difficult. Attributable risk fraction using prevalence of organic solvent exposure and RR showed the occupational burden of pre-clinical early neurotoxic health effect.