Previous research updated the mortality experience of North American synthetic rubber industry workers during the period 1944-1998, determined if leukemia and other cancers were associated with several employment factors and carried out Poisson regression analysis to examine exposure-response associations between estimated exposure to 1,3-butadiene (BD) or other chemicals and cancer. The present study used Cox regression procedures to examine further the exposure-response relationship between several unlagged and lagged, continuous, time-dependent BD exposure indices (BD parts per million (ppm)-years, the total number of exposures to BD concentrations >100 ppm ("peaks") and average intensity of BD) and leukemia, lymphoid neoplasms and myeloid neoplasms. All three BD exposure indices were associated positively with leukemia. Using continuous, untransformed BD ppm-years the regression coefficient (beta) from an analysis that controlled only for age was 2.9 x 10(-4) (p
Center for Nutrition and Toxicology, Department of Biosciences, Karolinska Institute, Novum, S-141 57 Huddinge and Department of Molecular Genome Research, Stockholm University, S-106 91 Stockholm, Sweden. kamila.plna2cnt.ki.se
Epichlorohydrin (ECH) is a simple 3-carbon epoxide of industrial importance. It has been shown to be genotoxic in several systems and carcinogenic in experimental animals. The aim of the present investigation was to study DNA adducts of ECH as a biomarker of occupational exposure to this chemical. 7-(3-Chloro-2-hydroxypropyl)guanine (7-CHP-guanine) was analysed in DNA from white blood cells using an anion exchange-based adduct enrichment protocol of the (32)P-post-labelling/HPLC-based assay. Blood samples were collected from seven workers handling ECH (exposed), nine workers not handling ECH but normally present in the premises where this chemical is used (potentially exposed) and 13 office and factory workers from locations in the plant where ECH is not handled (controls). 7-CHP-guanine was detected in five of the seven workers exposed to ECH (1.6-7.1 mol/10(9) mol nucleotides) and in two of the nine workers potentially exposed to ECH (0.8-1.5 mol/10(9) mol nucleotides). This adduct was not detected in any of the 13 controls. The difference in adduct levels between exposed workers and controls was statistically significant (Mann-Whitney test, P
Accumulation of artificial and natural radionuclides in the chains of food webs leading to non-predatory and piscivorous fish of the Yenisei River was investigated during one year before and three years after the shutdown of a nuclear power plant at the Mining-and-Chemical Combine (2009-2012). The activity of artificial radionuclides in the samples of biota ofthe Yenisei River (aquatic moss, gammarids, dace, grayling, pike) was estimated. The concentration of radionuclides with induced activity (51Cr, 54Mn, 58Co, 60Co, 65Zn, 141, 144Ce, 152, 154Eu, 239Np) decreased in the biomass of biota after the shutdown of the nuclear power plant; the concentration of 137Cs did not. Analysis of the accumulation factors (C(F)) allows us to expect the effective accumulation of 137Cs in the terminal level of the food web of the Yenisei River--pike (C(F) = 2.0-9.4), i.e. biomagnifications of radiocesium. Accumulation of artificial, radionuclides in non-predatory fish from gammarids was not effective (C(F)
[A decrease in the level of erythrocytes with micronuclei under the influence of pyrimidine and thiazolidine derivatives in the blood of persons who came under radiation exposure as a result of the accident at the Siberian Chemical Combine]
The authors have found that pentoxylum (pyrimidine derivative) and leucogenum (thyazolidine derivative) are capable or reducing the number of cells with micronuclei in the blood of people who suffered from the radiation accident at the radiochemical works of the Siberian chemical plant. The most effective decrease in the cells with micronuclei in adults was observed two weeks after treatment, while in children the same result was achieved with leucogenum on the third day.
In Norway, the largest reported quantities of radioactive discharges and radioactive waste containing naturally occurring radioactive material (NORM) come from the oil and gas sector, and smaller quantities of other NORM waste are also produced by industrial or mining processes. The Gulen final repository for radioactive waste from the oil and gas industry from the Norwegian continental shelf was opened in 2008 and has a capacity of 6000 tonnes. As of 1 January 2011, a new regulation was enforced whereby radioactive waste and radioactive pollution was integrated in the Pollution Control Act from 1981. This means that radioactive waste and radioactive pollution are now regulated under the same legal framework as all other pollutants and hazardous wastes. The regulation establishes two sets of criteria defining radioactive waste: a lower value for when waste is considered to be radioactive waste, and a higher value, in most cases, for when this waste must be disposed of in a final waste repository. For example, waste containing = 1 Bq/g of Ra-226 is defined as radioactive waste, while radioactive waste containing = 10 Bq/g of Ra-226 must be disposed of in a final repository. Radioactive waste between 1 and 10B q/g can be handled and disposed of by waste companies who have a licence for handling hazardous waste according to the Pollution Control Act. Alternatively, they will need a separate licence for handling radioactive waste from the Norwegian Radiation Protection Authority. The goal of the new regulation is that all radioactive waste should be handled and stored in a safe manner, and discharges should be controlled through a licensing regime in order to avoid/not pose unnecessary risk to humans or the environment. This paper will elaborate on the new regulation of radioactive waste and the principles of NORM management in Norway in view of the International Commission on Radiological Protection's 2007 Recommendations.
The author sets forth a gas chromatographic technique for the detection of monochloracetic acid (MCAA) and its sodium salts in the air, in skin washings, overalls extracts, and urine. The substances were identified as propyl ether. The analysis was performed on a chromatograph supplied with a plasma-ionizing detector on a 2 m-long glass column, with the chromatrone N-AW-DMCS. The detection capacity in the sample was 0.005 microgram/microliter, in the air for MCAA - 0.5 mg/m3, for MCAA sodium salt - 0.25 mg/m3. Standard deviation did not exceed 0.16. The technique was tested in industrial conditions.
Morphology of silicon carbide (SiC) fibres from the Norwegian SiC industry has been studied by scanning electron microscopy (SEM). The fibres are an unwanted side-product in SiC production. They represent a probable cause of the observed increased occurrence of lung diseases among SiC workers. The main aim of this work is to give a detailed description of the morphological variation of the fibres. Furthermore, it is important to study the occurrence of various morphological types with respect to job types and process parameters. SiC fibres accounted for >90% of all fibres observed. Eight categories of SiC fibres are described based on their morphology. The most frequent fibre category had a smooth surface and accounted for more than half of the observed SiC fibres. The diameter distributions of the eight fibre types were significantly different except for two of the categories. More than 99% of the SiC fibres observed were