Whole‐body exposures to a phosphoric acids aerosol: II. Food/water/weight effects in wild rodent and avian species

Abstract

Separate inhalation‐chamber studies were conducted to assess acute/subacute food intake (g), water intake (ml), and body weight (g) effects of four whole‐body phosphoric‐acids‐aerosol exposures in black‐tailed prairie dogs (Cynowys ludovicianus,); subacute effects of two exposures were studied in rock doves (Columba livia). A 95% red phosphorus/5% butyl rubber (RP/BR) mixture was burned to produce the aerosol. Each study involved (1) 3 RP/BR target concentration groups (0.0, 1.0, and 4.0 mg/L), (2) 24 prairie dogs or doves (8/group), with gender included as a factor in each study, and (3) a successive 3‐phase paradigm (2 d preexposure; 4 and 2 d of ∼80 min/d exposures to RP/BR for prairie dogs and rock doves, respectively; and 6 d postexposure). Results showed that in‐chamber atmospheres were uniform and acceptable for all exposures. No prairie dogs died, but 1 male rock dove died on d 3 postexposure to 4.0 mg/L aerosol. Concentration and gender main effects were significant for the acute (2 h out‐of‐chamber) food intake, water intake, and weight change of prairie dogs, with aerosol‐exposed and male rodents showing decrements. Cender and day main effects were also significant for the subacute (23 h/d) variables in prairie dogs; females weighed less than males, and reduced food/water/weight was evident for all animals during the 4 exposure days and first 3 postexposure days. For rock doves, subacute gender and day main effects, plus concentration x day and concentration × gender × day interactions, characterized the data. A transitive relationship was evident among RP/BR aerosol conditions (0.0 < 1.0 <4.0 mg/L) and mean decreased food intakes on the exposure days (d2 < d1). Enhanced postexposure water replenishment by female versus male doves exposed to 4.0 mg/L RP/BR aerosol was a main finding. Results are explained based upon a temporal model of phosphoric acid caused ulcers/edema. Effects are compared to prior evidence for albino rats, prairie dogs and rock doves; these are also discussed relative to certain human health and ecotoxicological literature.