In vitro predictions of skin absorption of caffeine, testosterone, and benzoic acid: a multi-centre comparison study.

To obtain better insight into the robustness of in vitro percutaneous absorption methodology, the intra- and inter-laboratory variation in this type of study was investigated in 10 European laboratories. To this purpose, the in vitro absorption of three compounds through human skin (9 laboratories) and rat skin (1 laboratory) was determined. The test materials were benzoic acid, caffeine, and testosterone, representing a range of different physico-chemical properties.

Color vision and occupational toluene exposure.

We examined the relationship between acquired color vision loss and exposure to toluene and total hydrocarbons among 125 male workers. Seventy-two toluene-exposed printers were compared with 34 workers from the same photogravure plant with ambient background exposure, and with 19 workers from a bookbinding plant located in the same town (nonexposed). Environmental mean toluene exposure level at workstation was estimated from individual 8-h sampling.

Estimation of the percutaneous absorption of styrene in an industrial situation.

Objective: This field study was designed to compare the level of styrene absorbed percutaneously with that absorbed by inhalation in a real situation in the fiberglass-reinforced polyester industry.

Methods: The study protocol consisted of comparisons of the patterns of urinary excretion of styrene metabolites by four groups of workers, all of whom performed the same task at the same time in the same workshop but wore the following different protective equipment: total protection with an insulating suit and mask, respiratory equipment only, percutaneous protection only, and no protection.

Results: The urinary excretion level of the group with total protection did not significantly differ from that of the group with respiratory protection only.

Cutaneous sensitization to some polyisocyanate prepolymers in guinea pigs.

Isocyanates are used extensively in the polyurethane industry. Pulmonary and dermal sensitization resulting from exposure to diisocyanates has frequently been reported, but the potential effects of polyisocyanates on health are less well known. Thus, since 1978, occupational exposure limits have been established for diisocyanates only.

Immunologic and renal markers among photogravure printers exposed to toluene.

Objectives: This study assessed immunologic and early renal effects of chronic toluene exposure.

Methods: In a longitudinal study of 92 printers and 74 referents, 145 subjects had pre- and poststudy samples of blood and urine taken for the following measurements: immunoglobulin E (IgE), antiglomerular basement membrane (anti-GBM) and antilaminin (anti-LAM) antibodies in blood; creatinine and beta2-microglobulin in blood and urine; and microalbumin, N-acetyl-b-D-glucosaminidase (NAG) and alanine-aminopeptidase in urine. Creatinine clearance was calculated according to the Cockroft-Gault formula.

Occupational exposure to solvents and hairy cell leukaemia.

Objectives: The role of occupational exposures in hairy cell leukaemia was investigated through a multicentre, hospital based, case-control study. This paper analyses the role of exposure to solvents other than benzene in hairy cell leukaemia.

Methods: The study included 226 male cases and 425 matched controls, exposure to solvents was evaluated by expert case by case review of the detailed data on occupational exposures generated by specific interviews.

Assessment of exposure to carcinogenic N-nitrosamines in the rubber industry.

Exposures to volatile nitrosamines were measured at 24 rubber manufacturing plants from 1992 to 1995. A total of 709 exposure measurements were taken in general areas or personal breathing zones to estimate exposure according to production types (seals, joints, tyres, gloves, etc.) and production steps, from mixing to storage.

Hairy cell leukaemia and occupational exposure to benzene.

Objectives: The role of occupational exposures in hairy cell leukaemia (HCL) was investigated through a multicentre, hospital based, case-control study. This paper analyses the role of exposure to benzene in HCL.

Methods: A population of 226 male cases of HCL and 425 matched controls were included in the study.

[Glomerular nephropathies and exposure to organic solvents--a case-control study].

Several studies have suggested that exposure to organic solvents is associated with glomerular nephropathies (GN), but this relationship remains controversial. A case-control study of 298 biopsy-proven cases and 298 hospital controls, matched for year of birth, sex, origin, and place of residence, was conducted between 1989 and 1991 in five hospitals in the Paris area : 82 cases of membranous glomerulopathy were included ; 100, nephrotic syndrome with either minimal change nephropathy or focal and segmental hyalinosis (MCN/FSH); and 116, IgA nephropathy (IgA N). Subjects were interviewed about their lifelong occupational and non-occupational activities.

Organic solvent exposure may increase the risk of glomerular nephropathies with chronic renal failure.

Background: Several studies have suggested that exposure to organic solvents is associated with glomerular nephropathies (GN), but this relationship remains controversial.

Methods: A case-control study of 298 biopsy-proven cases and 298 hospital controls, matched for year of birth, sex, origin, and place of residence, was conducted between 1989 and 1991 in five hospitals in the Paris area: 82 cases of membranous glomerulopathy were included; 100, nephrotic syndrome with either minimal change nephropathy or focal and segmental hyalinosis (MCN/FSH); and 116, IgA nephropathy (IgA N). Subjects were interviewed about their lifelong occupational and non-occupational activities.

Occupational exposure to polycyclic aromatic hydrocarbons and the risk of bladder cancer: a French case-control study.

Background: The risk of bladder cancer has been shown to be increased in occupations which are likely to involve exposure to polycyclic aromatic hydrocarbons (PAH), but up to now, most studies have considered this exposure in terms of job title.

Methods: A hospital-based case-control study of 658 male cases of bladder cancer and 658 male controls was carried out in five areas of France from 1984 to 1987. For each subject, occupational exposure to PAH was assessed from questionnaires by an expert according to a semi-quantitative index of exposure.

[Exposure of urban bus drivers to traffic pollution].

Two measurement campaigns aimed at measuring the air pollutant emissions of vehicles (carbon monoxide, nitrogen oxides, lead, benzo[a]pyrene and formaldehyde) have been carried out using on-board sampling or analysis equipment in public buses in two major French towns. The study had a double objective: (i) to assess the occupational exposure through pollutant measurements in the breathing zone of the drivers at their working posts, (ii) to compare the quality of the air sampled outside, either at the bus front (current position of the ventilation air intake), or on the vehicle roof. Carbon monoxide measurements were performed with several Ecolyser (electrochemical detection) standardized with a Mahiak Unor 6N infra-red non-dispersive analyser and nitrogen mono- and dioxide with AC 30 M Environment S.

Occupational risks of bladder cancer in France: a multicentre case-control study.

The relationships between occupational risk factors in France and bladder cancer were assessed from a hospital-based case-control study conducted between 1984 and 1987 in five regions representing various industries, including mining, textile manufacture, metallurgy and the production of rubber and chemicals. The study concerned 765 cases (658 men and 107 women) and the same number of controls. Odds ratios (OR) adjusted for matching variables (age, place of residence and hospital), and tobacco smoking were estimated by unconditional logistic regression.

Retrospective evaluation of occupational exposure to organic solvents: questionnaire and job exposure matrix.

Correct retrospective assignment of subjects to an exposure category is affected by a variety of problems: 1) lack of an objective lifetime measurement; 2) dependence upon the accuracy and thoroughness of the job description; 3) heavy reliance upon the knowledge of experts. The aim of the study was the quantification of the performance of a job exposure matrix (JEM) in evaluating solvent exposure, using expert judgements as the reference method. The sources of discrepancies between the two methods were analysed within the framework of two community-based case-control surveys.

The carcinogenic effect of a series of petroleum-derived oils on the skin of mice.

Six groups of 30 Swiss mice were treated by application to the skin in the dorsolumbar region two times a week for 12 months of a "white oil" and five samples of petroleum oils derived from the same "crude" (Middle East), which were collected in the same refinery at different stages of "solvent treatment" and which form a homogeneous series with increasing concentrations of polyaromatic hydrocarbons (PAH). The macroscopic and histopathologic examination of the animals (skin and organs) up to 18 months shows the following effects with respect to the 60-mouse control group: --a marked irritating effect for the "aromatic extract," the "distillate," and a "mixture" of intermediary concentration between "distillate" and "raffinate," --a definite tumorigenic effect on the skin (papillomas, kerato-acanthomas, squamous cell carcinomas, and fibrosarcomas) of the "aromatic extract" and the "distillate." The biological answer is in significant association with the PAH concentration of the samples, which is estimated by different analytical methods: viscosity index, percentage of aromatic carbon, "total PAH" according to a gravimetric method, and benzo[a]pyrene concentration.

N-nitrosodiethanolamine in antifreeze.

Carcinogenic N-nitrosodiethanolamine has been found at concentrations varying from 15 to 5700 mg/liter in several leading French brands of antifreeze. Moreover, mixtures of antifreezes which, separately, are innocuous, can form this nitrosamine which appears to arise from interaction of triethanolamine derivatives with sodium nitrite. It is recommended that sodium nitrite be abandoned as an anticorrosion additive.

Meat wrapper's asthma: identification of the causal agent.

Meat wrapper's asthma is a typical example of occupational asthma due to emissions from chemical products. The authors report three new cases due to the use of the now classic meat packaging techniques in supermarkets. The chemical agents involved were identified.

Irritant dermatitis from diallylglycol carbonate monomer in the optical industry: clinical and experimental studies of cutaneous tolerance and chemical investigations.

The diallylglycol carbonate monomer causes dermatitis due to irritation in the optical industry. Cutaneous intolerance may effect as many as 70% of the exposed persons employed. Almost all control subjects who where patch-tested showed irritation at a 2% concentration.

[Carcinogenic polycyclic aromatic hydrocarbons in petroleum products: possible prevention of mineral oil cancer].

A real epidemy of cutaneous cancer has appeared from 1954 in a french area specialized in the metal machining industry (valley of the Arve, Haute-Saoie). Two investigations have been carried out: - one, of clinical and epidemiological nature over a period of 15 years, has recorded 133 casesof spinocellular epitheliams often located in the scrotum and has allowed to estimate the hazard for the population of this region at 25 per 100 000 (that is to say 36 times more than for the general population). - the other, of chemical nature, has revealed on one hand that the new cutting oils, such as delivered to the utilizers, rather frequently contain benzo [a] pyrene (concentration : 0,5 to 150 ug/l), and on the other hand that the used oils are inclined to grow richer in carcinogenic hydrocarbons.