The use of nanoparticles (NPs) in industry is increasing, bringing with it a number of adverse health effects on workers. Like other chemical carcinogens, NPs can cause cancer via oxidative DNA damage. Of all the molecules vulnerable to oxidative modification by NPs, DNA has received the greatest attention, and biomarkers of exposure and effect are nearing validation. This review concentrates on studies published between 2000 and 2012 that attempted to detect oxidative DNA damage in humans, laboratory animals, and cell lines. It is important to review these studies to improve the current understanding of the oxidative DNA damage caused by NP exposure in the workplace. In addition to examining studies on oxidative damage, this review briefly describes NPs, giving some examples of their adverse effects, and reviews occupational exposure assessments and approaches to minimizing exposure (e.g., personal protective equipment and engineering controls such as fume hoods). Current recommendations to minimize exposure are largely based on common sense, analogy to ultrafine material toxicity, and general health and safety recommendations.

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(1-BP) in SD rats were investigated. LC50 for four-hour exposure was 14,374 ppm (95% confidence limit: 13,624-15,596 ppm). It was revealed to be irritating to the eyes with lacrimation in all fourhour exposure rats. No other abnormal clinical signs and gross findings related to the 1-BP exposure were observed. An experiment on repeated exposure to 0, 50, 300, and 1,800 ppm for six hrs/day, five days/week, for eight weeks was conducted.A decrease in body weights and increase in relative liver weight in both male and female rats were observed in the 1,800 ppm exposure group (p<0.001 vs. control group). No other significant changes in feed consumption, urinanalysis, hematology and serum biochemistry were observed. Histopathological examinations did not reveal any 1-BP-related changes. (J Occup Health 1999; 41: 121-128)

ObjectivesA hazard assessment of di(2-ethylhexyl) phthalate (DEHP), a commonly used workplace chemical, was conducted in order to protect the occupational health of workers. A literature review, consisting of both domestic and international references, examined the chemical management system, working environment, level of exposure, and possible associated risks. This information may be utilized in the future to determine appropriate exposure levels in working environments.MethodsHazard assessment was performed using chemical hazard information obtained from international agencies, such as Organization for Economic Cooperation and Development-generated Screening Information Data Set and International Program on Chemical Safety. Information was obtained from surveys conducted by the Minister of Employment and Labor (“Survey on the work environment”) and by the Ministry of Environment (“Survey on the circulation amount of chemicals”). Risk was determined according to exposure in workplaces and chemical hazard.ResultsIn 229 workplaces over the country, 831 tons of DEHP have been used as plasticizers, insecticides, and ink solvent. Calculated 50% lethal dose values ranged from 14.2 to 50 g/kg, as determined via acute toxicity testing in rodents. Chronic carcinogenicity tests revealed cases of lung and liver degeneration, shrinkage of the testes, and liver cancer. The no-observed-adverse-effect level and the lowest-observed-adverse-effect level were determined to be 28.9 g/kg and 146.6 g/kg, respectively. The working environment assessment revealed the maximum exposure level to be 0.990 mg/m3, as compared to the threshold exposure level of 5 mg/m3. The relative risk of chronic toxicity and reproductive toxicity were 0.264 and 0.330, respectively, while the risk of carcinogenicity was 1.3, which is higher than the accepted safety value of one.ConclusionsDEHP was identified as a carcinogen, and may be dangerous even at concentrations lower than the occupational exposure limit. Therefore, we suggest management of working environments, with exposure levels below 5 mg/m3 and all workers utilizing local exhaust ventilation and respiratory protection when handling DEHP.

The subchronic toxicity of 1,3-dichloro-2-propanol (1,3-DCP) was investigated in Fischer 344 rats after 13 weeks of repeated, whole-body inhalation exposure. Groups of 10 rats of each sex were exposed to 1,3-DCP vapor by whole-body inhalation exposure at concentrations of 0, 5, 20 or 80 ppm for 6 h/day, 5 days/week for 13 weeks. All of the rats were sacrificed at the end of the treatment period. During the test period, clinical signs, mortality, body weights, food consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights and histopathology were assessed. At 80 ppm, a decrease in the body weight gain, an increase in the urine protein and leukocyte counts and an increase in the liver and kidney weights were observed in both genders. Hematological and serum biochemical investigations revealed decreases in hemoglobin (HB), hematocrit (HCT), mean corpuscular volume (MCV) and mean corpuscular HB, as well as increases in the platelet (PLT) count, serum aspartate aminotransferase and alanine aminotransferase. The number of white blood cells was significantly lower in males than in controls, but this was not the case in females. Histopathological alterations included an increase in the incidence of multifocal necrosis, inflammation, pigmentation, biliary hyperplasia and the foci of cellular alteration of the liver and chronic nephropathy and protein cast of the kidney. At 20 ppm, decreases in HCT and MCV and increases in the liver and kidney weights were observed in both genders. A decrease in the HB of females and an increase in the PLT count of females were also observed. Histopathological alterations included slight increases in the incidences of hepatic necrosis, hepatic inflammation and chronic nephropathy. At 5 ppm, we found decreases in the MCV of males and the HB of females, as well as an increase in the liver weight of both genders. In the present experimental conditions, the target organs were determined to be the liver, kidney and blood cells in rats. The no-observed-adverse-effect level was considered to be <5 ppm/6 h/day and the low-observed-adverse-effect level was believed to be 5 ppm/6 h/day in rats.