Pesticides' Cornea Permeability-How Serious Is This Problem?

Background: A total of 348 pesticides from different chemical families (carbamates, organochlorines organophosphorus compounds, pyrethroids, triazines and miscellaneous) were investigated in the context of their cornea permeability and potential to cause eye corrosion. Methods: Multivariate models of cornea permeability based on compounds whose cornea permeability has been determined experimentally were proposed. The models, applicable to compounds across a relatively broad lipophilicity range (e.g., pesticides with octanol-water partition coefficient log P up to ca. 8), assume a reverse-parabolic relationship between cornea permeability and lipophilicity, expressed as XLOGP3; other main descriptors present in the models are log D at pH 7.4 and polar surface area (PSA). Results: It appears that the trans-corneal transport of all studied pesticides is possible to some degree; however, it is more difficult for the majority of highly lipophilic pesticides from the organochlorine and pyrethroid families. The same set of 348 pesticides was also evaluated for their eye-corrosive potential using novel artificial neural network models involving simple physico-chemical properties of the compounds (lipophilicity, aqueous solubility, polar surface area, H-bond donor and acceptor count and the count of atoms such as N, NH, O, P, S and halogens). Conclusions: It was concluded that eye corrosion is an issue, especially among the pesticides from organochlorine and organophosphorus families.