No abstract

The aim of this work was to establish whether workers at sawmills where chlorophenol-containing anti-stain agents had been previously used were still exposed to chlorophenols. A gas chromatographic-mass spectrometric (GC-MS) procedure for the determination of chlorophenols in urine was developed. Chlorophenols were determined from hydrolysed urine as acetylated derivatives and determined by GC-MS using selected ion monitoring (SIM). Isolation of the chlorophenols with toluene gave the best extraction efficiencies (65-119%). Stability tests at -20 degrees C showed no degradation of the chlorophenols studied during 6 months. The limit of quantification was 3.6 ng mg-1 creatinine for 2,4,6-trichlorophenol, 5.5 ng mg-1 for 2,3,4,6-tetrachlorophenol and 3.6 ng mg-1 for pentachlorophenol. Traces of 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol were found both in previously exposed workers and in non-exposed controls, the urinary concentrations ranging from 1.1 to 15.9 ng mg-1 creatinine. The concentrations of urinary chlorophenols in previously exposed workers were of the same magnitude as those found in non-exposed controls and in the general population. The results show that it is unlikely that sawmill workers would be currently occupationally exposed to chlorophenols or polychlorinated dibenzo-p-dioxins and dibenzofurans via a contaminated work environment.

A total of 100 workers, 86 from the glass-fibre-reinforced plastics (GRP) industry, 11 from polystyrene production and 3 from polyester resin coating manufacture, were examined for occupational skin hazards and for evaluation of skin protection. The workers had been exposed to many chemicals. Those working in the GRP industry had also been exposed to glass fibre and to dust produced by finishing work. 94% used protective gloves. 22 workers, all employed in the GRP industry, had contracted occupational skin disorders. 6 had allergic and 12 irritant contact dermatitis. 4 workers had an accidental injury caused by a peroxide catalyst, fire, hot air and constant mechanical friction. Allergic dermatoses were due to natural rubber (latex) (4 cases) in protective gloves, phenol-formaldehyde resin (1 case) and cobalt naphthenate (1 case). Irritant hand dermatoses (5 cases) were caused by the combined hazardous effect of unsaturated polyester or vinyl ester resins, organic solvents, glass fibre and dust from finishing work on the skin. Other cases of irritant dermatoses (7 cases) were due to the dust, promoted by mechanical friction of clothes. Skin disorders in the GRP industry were common (26%) but the symptoms were mild and only 3 patients had been on sick leave because of occupational skin disease.

The exposure of road pavers to total particulates, bitumen fumes, semivolatile organic compounds (SVOCs), polycyclic aromatic hydrocarbons (PAHs), low-molecular-weight amines, styrene, and 1,3-butadiene was studied at 13 paving sites where 11 different asphalt mixtures were laid. Researchers analyzed 1-hydroxypyrene in the workers' pre- and postshift urine samples. The arithmetic mean concentrations of total particulates, bitumen fumes, SVOCs, and PAHs in the breathing zone of road pavers were 0.6 mg/m3, 0.29 mg/m3, 5.6 mg/m3, and 5.03 microg/m3, respectively. The highest bitumen fume concentrations (2.65 mg/m3) were measured in manual mastic laying, that is, when the paving temperature was highest. More than 90% of air impurities measured were in the vapor phase. Workers laying surface dressing were exposed to the highest SVOC concentrations (27.8 mg/m3). The paving temperature and the concentrations of bitumen fume correlated positively, but the weather conditions significantly affected the workers' exposure; for example, increased wind velocity resulted in lower concentrations of SVOCs and PAHs. Job title was not found to be a significant determinant of exposure, but exposure to bitumen fume and greater than or equal to four-ring PAHs among manual mastic pavers, and that to SVOCs and total PAHs among surface dressing workers, were significantly higher than among other pavers. Exposure during road paving operations was, on average, more than 10-fold higher to PAHs than was the exposure of a traffic controller (0.34 microg/m3) caused by automobile exhausts from background traffic. The PAHs were comprised mainly of two- and three-ring compounds. The concentrations of amines, and impurities from polymer modified bitumens, styrene, and 1,3-butadiene were below detection limits. Urinary 1-hydroxypyrene concentrations were higher among road pavers than among office workers serving as referents.

of m-xylene in man: General features of absorption, distribution, biotransformation and excretion in repetitive inhalation exposure. Scand. j. work environ. & heaLth 5 (1979) 217-231. Sedentary volunteer subjects were exposed to an m-xylene concentration of a:bout 3.9 mmol/m 3 over five successive days, 6 hid. It was noted that about 6{) Ofo of the inhaled xylene was retained in the lungs. The estimated daily uptake of xylene was recovered nearly quantitatively as methylhippuric acid in the urine. Other pathways of xylene excretion played a minor role. The rate of 2,4-xylenol excretion shortly after a day's exposure was about 1-2 % of that for methylhippuric acid excretion, and pulmonary excretion of unchanged xylene amounted to about 4 0/0 of the estimated uptake. In the blood, xylene was mainly associated with serum proteins, and only small amounts resided in the cells. Postexposure excretion of xylene in expired air and the urinary excretion of methylhippuric acid were initially rapid (elimination half-time about 1 h), and after an intermediate phase it attained, some 6-16 h after the exposure, a slow phase of elimination (half-time about 20 h). These observations are congruent with the concept that xylene is distributed to at least two main tissue compartments in the body. The slow elimination takes place from tissues with a high xylene solubility and a small perfusion, for example, adipose tissue; in this compartment cumulation of xylene occurs over repeated exposures. Under the conditions studied no signs of saturation of the metabolic pathways or renal excretion were noted.