Ocular irritancy responses to various pHs of acids and bases with and without irrigation.

Acids and alkalies were instilled into the eyes of 2 groups of rabbits; the eyes of one group were washed with tap water 30 s after exposure. Damage seen in washed and unwashed eyes was not always related to pH. Some strong acids with greater acidity than pH 2.5 produced opacities while 0.3% hydrochloric acid with a pH of 1.28 produced no ocular damage. Phenol (5%) and acetic acid (5%) with pHs greater than 2.5 produced damage equivalent to or greater than that produced by equal concentrations (w/v) of the mineral acids. All alkalies with pHs ranging from 11.5 to 13.5 produced opacities and other ocular damage of different degrees depending upon the alkali and its concentration. For example, low concentrations of some alkalies in the pH range from 11.3 to 12.8 produced no ocular changes. The duration of the corneal opacities produced by phenol, 1% sodium hydroxide, acetic acid and anhydrous sodium carbonate and the onset of corneal opacity produced by 5% sulfuric acid, the weak acids and 1% sodium hydroxide were reduced as a result of washing the test eyes 30 s after instillation of the test material. These data suggest that acidity and alkalinity of the test material are not the only factors to be considered in relation to a substances' capacity to produce severe ocular injury. The concentration of the test chemical and its period of contact with the eye prior to washing are also important.

Percutaneous absorption of radiolabeled TRIS from flame-retarded fabric.

Surface tris-(2,3-dibromopropyl) phosphate (TRIS) was removed from flame-retarded polyester fabric by benzene-hexane extraction and replaced with 14C-TRIS. Sections of the radiolabeled fabric (10 X 12 cm) were placed in contact with the clipped skins of rabbits, and urine and feces were collected over a 96 hr period. The cloths were allowed to remain dry or were moistened with either urine or simulated sweat. A similar collection of urine and feces was performed following i.v. injection of 14C-TRIS. From the results of these experiments, it can be calculated that up to 17 percent of the radiolabel on the cloth penetrated rabbit skin over the 96 hr period of exposure. Most of the excreted radiolabel appeared in the urine, with the kidney being the organ of highest specific radioactivity. The highest absorption of radiolabel occurred in the urine-moistened cloth group. Moistening the cloth with simulated sweat produced no increase in absorption over that seen with dry cloth.

Potential biological hazards of commercially available cleansers for dentures.

Thirteen representative denture cleansers were selected from among more than 32 retail products to be tested for potential hazard and toxicity to humans. Products were subjected to toxicological analyses by using the biological tests (acute oral toxicity in rats, eye and skin irritation in rabbits) specified in the Federal Hazardous Substances Act Regulations. All products were eye irritants with ranges from slight to severe. Three produced a primary skin irritation response (one was corrosive), while five of the denture cleansers produced oral LD50 values below 5 g/kg. Furthermore, a provisional upper gastrointestinal irritancy test used in rabbits indicated that eight of the denture cleansers produced upper gastrointestinal irritation, which was, in general, dose-related.

Renal and testicular damage following dermal application of the flame retardant tris (2,3-dibromopropyl) phosphate.

Tris(2,3-dibromopropyl) phosphate (TRIS) was the most popular flame retardant chemical used in children's sleepwear. Acute toxicological data indicated that TRIS was low in toxicity. Since human exposure to TRIS-treated fabrics could occur for long periods of time, a subchronic study was undertaken to obtain additional information. The dermal application of TRIS (neat) at a dose of 1 ml/kg (2.27 g/kg) to the clipped backs of albino rabbits, once each week for 3 months, resulted in testicular atrophy and chronic interstitial nephritis in males. Females did not show any adverse effects.

Detergent toxicity survey.

A survey of over 249 detergent products involving biological testing, chemical analyses, and product label reviews has been conducted from 1971-1976 for determining compliance with the Federal Hazardous Substances Act. Test results for 145 detergent products having both chemical and biological data were examined. All of the tested detergents were rabbit eye irritants. Forty-seven per cent were also either rabbit primary skin irritants or corrosives. Eighty-one per cent were either rabbit esophageal test irritants or corrosives, and 80 per cent had rat oral toxicities 5g/kg or less.

Appraisal of existing methodology in aspiration toxicity testing.

New methods or modifications of currently used methods in aspiration toxicology must be capable of accurately assessing the hazard and toxicity potentials of those products which are capable of being aspirated. The methods evaluated in the rat were intratracheal injections,intravenous injections, and modifications of the Gerarde technique. A product containing petroleum distillates and a standard viscosity petroleum distillate sample were administered to Osborne-Mendel rats, rabbits, and guinea pigs in ml/kg doses. The utility of the methods was determined by comparing lung weight increases, lung-body weight ratios, gross pathological lung changes, and mortality. The modified Gerarde technique showed the best potential for predicting aspiration hazard and toxicity based on the severity of the reactions which, using a radiolabeled oil, was shown to be a function of the amount of product which enters and reacts with the lungs. The influence of preventing the swallowing reflex to assure aspiration of the oil was assessed in the rat. The results show that less than 10% of the dose is aspirated when the swallowing reflex occurs. Methods of sacrifice were investigated for an effect on rat lung weight. No tested method except stunning with cervical dislocation produced an effect. Tests were conducted on rats and rabbits to determine differences in lung reactivity to the influence of inhalation anesthetics, pentothal sodium, or no anesthesia in response to petroleum distillate administration and to determine which test species is the better animal model. The resuls indicate that the rat is the better test model because of degree of lung reaction, size, and economy, and that inhalation anesthesia with ether is preferable over the other choices.

Evaluation of the teratogenic potential of a spray adhesive in hamsters.

Pregnant Syrian hamsters were placed in a 100-1 static inhalation chamber for 30 min twice daily on days 5-10 of gestation and exposed to 8.0 +/- 0.13, 11.6 +/- 0.11,or 13.23 +/- 0.49 g of "Foil Art Adhesive" and killed on day 14. Controls were placed in adjacent identical chambers but received no spray. The spray adhesive was toxic but not teratogenic at the doses administered. Maternal alopecia occurred upon exposure to the 2 highest dose levels, and 1 female died during exposure to the highest dose level. Fetal survival was not affected. Mean fetal weight was significantly decreased after exposure to all 3 dose levels, and delayed skeletal development occurred but was not dose related.