A health hazard evaluation of workers exposed to solvents during the re-furbishing of chemical rail-tankers

Abstract

This study was aimed at evaluating the health hazards of workers exposed to solvents during the re-furbishing of chemical rail-tankers. The process of re-furbishing comprises of three main and sub processes that requires the application of three different solvent products at various time intervals. Two of the three main processes were conducted within the tanker, defined as a confined space, and the third was conducted on the dome area, situated on the outside middle top area of tanker. The main chemical composition of the solvent products used included, xylene, toluene, trichloroethylene, methylene chloride, methyl ethyl ketone (MEK) and petroleum solvent. Various different combinations of chemical compositions, per solvent product, were found. During the assessment of the solvent exposures, as prescribed by the National Institute for Occupational Safety and Health Manual of Analytical Methods NOSH Manual of Analytical methods, results for both personal and environmental / area air samples were found to be in violation of the occupational exposure limit (OEL) for mixtures, as it has exceeded the unity of one (1). This result was further supported by the high urine content of biological markers, which are reflected in the biological exposure index, for the majority of solvents. The most frequent complaints experienced among the majority of exposed workers included, headaches, dizzy spells, a feeling of fatigue, drunkenness and eye irritation. A lesser percentage experienced nausea (feeling like vomiting), had a sense of irritability and breathing problems. Control measures, aimed at limiting exposures, were found to be inadequate or non-existent as some workers indicated that they were required to purchase their own personal protective equipment. No training or awareness in the safe use, handling, storage and associated health effects has been provided to workers exposed to solvents. The study highlights numerous limitations and concerns, which sets the platform for future studies within similar work environments.