A swine producer reported severe chemical skin burns and high death losses when a group of finisher pigs was exposed to a combination of hydrated lime and sodium bicarbonate. Hydrated lime, an alkalinizing agent commonly used in industry and agriculture, is derived from limestone. We report clinical and experimental evidence that sodium bicarbonate can intensify the caustic effects of this form of lime.

Young, recently weaned pigs were implanted with subcutaneous vascular access ports in experiments designed to determine the relative bioavailability of lead from contaminated soils. In nine experiments, a total of 72 subcutaneous vascular access ports were implanted. Complications were observed in 38.9% of the implanted pigs. Changes in the protocol were implemented in an effort to reduce the rate of complications. The majority of complications were septic processes, including localized infections around the site of the catheter and injection port, hematogenous pulmonary abscessation, endocarditis, and septic arthritis. Staphylococcus aureus, S. hyicus, b-hemolytic Streptococcus species, and Actinomyces pyogenes were cultured from septic processes in these pigs. Our findings suggest that the health of the skin at the time of surgery, the experience of the surgeon, and the immunologic status of the animal influence the risk of septic complications in pigs implanted with subcutaneous vascular access ports.

Bioavailability of lead (Pb) has become an issue in quantifying exposure of sensitive populations and, where necessary, establishing cleanup levels for contaminated soil. Immature swine were used as a model for young children to estimate the degree to which Pb from two fully characterized composite samples from the Smuggler Mountain Superfund Site in Aspen, Colorado may be bioavailable to resident children. The composite soils contained 14,200 and 3870 μg Pb/g of soil. Relative and absolute enteric bioavailabilities of Pb in soil (oral dose groups of 75, 225, and 675 μg Pb/kg body wt/day) were estimated by comparison with an orally administered soluble Pb salt (lead acetate = PbAc2·3H2O) (dose groups of 0, 75, and 225 μg Pb/kg body wt/day) and an intravenously administered aqueous solution of Pb (100 μg Pb/kg/day) from the same trihydrate salt administered daily for 15 days to 50 juvenile swine. The biological responses (area under the blood Pb concentration–time curve, and the terminal liver–, kidney–, and bone–lead concentrations) produced by Pb from PbAc2·3H2O and lead-contaminated soils were determined. This study revealed Pb from soil containing 14,200 μg Pb/g of soil had a bioavailability relative to Pb from PbAc (RBA), ranging from 56% based on the area under the blood lead concentration–time curve (AUC) versus dose, to 86% based on calculations from liver–Pb loading versus dose. Similarly, Pb from soil containing 3870 μg Pb/g of soil had an RBA ranging from 58% based on the AUC versus dose, to 74% based on calculations from liver– and kidney–Pb loading versus dose. Bioavailability of Pb in soils may be more or less than EPA's default RBA of 60%, therefore, measuring site-specific RBAs provides a basis for improved exposure and risk assessment.