Paul A. Palmisano

Untaxed whiskey and fetal lead exposure.

Summary A 10-week-old infant with evidence of neurologic defects, intrauterine growth retardation, and postnatal failure to thrive was studied for abnormal lead accumulation because of a maternal history of long-term ingestion of untaxed whiskey. After challenge doses of CaEDTA, the infant and the mother each excreted an abnormally large amount of lead in the urine. These data provide suggestive evidence of transmission of lead transplacentally. Because of the widespread ingestion of untaxed whiskey in the southeastern United States, intrauterine lead exposure may be a cause of fetal and neonatal disease.

Central Nervous System Salicylate

The poor correlation between clinical salicylate toxicity and serum blood levels is reapproached in light of recent evidence linking clinical severity with initial volume of distribution (Vd). It is recognized that two variables alter salicylate Vd in such manner that serum salicylate levels are misleading (thus, the change in Vd is not detected by present methods). These variables are serum protein binding and the pH-dependent ionized/un-ionized ratio in the unbound salicylate fraction. Measurements of salicylate concentration in the cerebro spinal fluid (CSF) would circumvent these variables, but would be clinically impractical. Thus, an alternative is sought to the inexact total serum salicylate levels and the impractical CSF salicylate levels for assessment of the severity of salicylate poisoning. This study indicates that, in dogs, serum unbound salicylate levels closely reflect CSF salicylate levels, even as a decrease in serum protein binding is in progress. However, serum unbound salicylate concentration does not reflect CSF salicylate concentration as a decrease in serum pH is elicited (CSF salicylate actually increased as serum unbound salicylate decreased). On the other hand, serum unbound salicylate measurement would seem preferable to total serum salicylate measurements now used in that the total value decreased markedly as either protein binding change or acidosis produced a change in distribution and the resultant increase in CSF salicylate.

Hospitalization as a measure of clinical toxicity

Acute animal toxicity data are useful in comparing a series of compounds with regard to a given toxic endpoint. Such information is not obtainable from human populations, and clinicians must often be guided by empiric judgement in treating acute ingestions. This experimental survey compared the calculated percent of cases hospitalized for 12 common substances ingested by young children as reported by the National Clearinghouse for Poison Control Centers for 1975-1976. Such ratios are offered as measures of clinical toxicity and as helpful modes of input in guiding patient management.