One issue increasing potential toxic results is the application of resorcinol to injured skin Cassano et al. Surviving F 0 parental and F 1 following choice rats underwent full gross necropsy following the breeding interval seven F zero males per group , following completion of weaning of F 1 pups F zero females , following scheduled necropsy of F zero females remaining seven F zero males per group , on PND 28 F 1 exposed pups , or on PND 30 or 70 F 1 pups chosen for behavioural testing.
Animals that died confirmed hyperaemia and distension of abdomen and intestine, while there have been no gross lesions at necropsy in survivors Flickinger, In one other study with CFY rats. Most of the research are of sufficient high quality and acceptable for risk characterization functions.
There were no printed animal studies showing thyroidal effects with a dose—response relationship that might be used for a tolerable intake. In the body of a full life cycle toxicity take a look at OECD TG , Lima observed no antagonistic effects after 48 h of exposure on the highest concentration examined, zero. Furthermore, Cronin et al. The fish and pond snails had been positioned instantly into the aquaria, whereas the remaining 5 species were segregated in several baskets and suspended within the aquaria. The solely investigation into this finish-level is that from the dose range-discovering study reported in sections 8.
The microscopic examination of the thyroid gave minimal modifications follicular hyperplasia , which were statistically not vital between controls and individual dose teams RTF, In vitro research have been performed to evaluate the results of resorcinol on thyroid perform. In excessive-dose teams, a decrease in body weight and decreased survival were famous. Owing to concern in regards to the thyroid effects of resorcinol, which have been shown in human studies to happen at excessive doses, this finish-point in particular has been the purpose of focus in several research. In most of the older studies, the consequences of resorcinol exposure on the thyroid gland are conflicting. It has been advised that thyroid effects seem to be depending on an administration route that allows for continued systemic exposure e.
Two lengthy-time period research with Swiss mice or NZW rabbits, the place the animals had been handled with zero. In an in vitro. In an investigation in three human volunteers utilizing situations similar to those used in hair dyeing, 14 C-ring-labelled 1. This means that only a small quantity of resorcinol penetrates the pores and skin through the precise process of hair colouring.
In each species, there were no adverse results on ultimate imply physique weights, haematology, or clinical chemistry parameters, and no chemical-associated gross or microscopic lesions had been observed. In one other research, rats had been exposed to zero or zero. No thyroid hormone measurements were performed.
Complete restoration in all animals occurred within 1—1. Of the following studies, the repeated-dose toxicity studies that have been deemed to be most relevant to the chance evaluation are summarized in Appendix 6. In a research performed by NTP , five female and male F rats were dosed with resorcinol in deionized water via gavage at zero, High-dose females had significantly decreased absolute and relative thymus weights. No other biologically significant differences in organ weights had been observed. In distinction to those findings, Eastin et al.
These figures agree nicely with the above publicity estimate based on the Yeung et al.