Ocular toxicity arsenicals

British Anti-Lewisite (BAL), also known as Dimercaprol, is a chelating agent than can reduce systemic effects from Lewisite. BAL works by binding the arsenic group in Lewisite and displacing it from tissue binding sites. If applied topically within minutes, after decontamination, BAL may prevent or reduce the severity of cutaneous and ocular toxicity (8). 

Owens, E.J., Weimer, J.T., Ballard, T.A., Ford, D.F., Samuel, J.B., Hopcus, M.W., Merkey, R.P., and Olson, J.S. Ocular, cutaneous, respiratory and Intratracheal toxicity of solutions of CS and EA 3547 In glycol and glycol ether in animals. U.S. Army Medical Research Laboratory, Edgewood Arsenal, Md. 

A report on an Edgewood Arsenal study on the toxicology of RDX and HMX solns in di-methylsulfoxide, cyclohexanone and acetone states that a study of the toxicology of the expls RDX and HMX in acet, cyclohexanone, and pure and technical grade dimethylsulfoxide (DMSO) was initiated to establish whether there is any danger to plant personnel that handle such mixts. The report contains a review of the existing literature on each expl and on each solvent. It also describes tests that were conducted to establish the intravenous toxicity of the expls in DMSO, skin potential, and the ocular effects of the expls in each solvent. All of these tests were conducted on animals (Ref 77)... 

Both patients had clear anatomical causes for blindness, and unilateral (rather than bilateral) blindness suggested a limited role for systemic arsenic toxicity. Nevertheless, a weak contribution of ocular arsenic toxicity should not be ruled out. Both arsenic trioxide and all-trans retinoic acid can increase intracranial pressure, resulting in pseudotumor cerebri and a secondary increase in intraocular pressure, which may augment retinal injury. Also, arsenic trioxide can cause vasoconstriction and worsen retinal artery occlusion. Finally, elemental arsenic was detected in the eyes at 30-50% of the plasma concentration, a ratio comparable to that in cerebrospinal fluid. This may have direct retinal toxicity, especially with the high peak concentrations associated with intravenous arsenic trioxide. Full ophthalmic evaluation is recommended in patients receiving longterm or intravenous arsenic trioxide. 

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