Phosphamidon poisoning

The acetonitrile layers are mixed and poured into another separatory funnel. In cases of dimethoate, Dasanit, phosphamidon and DDVP poisonings, the three acetonitrile fractions are combined and evaporated to dryness, and the residue is taken up in one milliliter of acetone. Further extraction of acetonitrile is avoided as this results in appreciable loss of pesticides. The acetonitrile layer is diluted with water to ten times of its original volume. Twenty-five ml. of saturated sodium sulfate solution is added to this solution and extracted three times with twenty-five milliliter-portions of n-hexane previously saturated with distilled water. The separated n-hexane layers are combined and then concentrated to two milliliters on a warm water bath. 

The distribution data of a case of poisoning by phosphamidon recorded in serial number 24 in Table III indicates that comparatively large amounts of phosphamidon was detected in the lung... 

Awareness of the dose necessary is, as always, crucial. In Canada an OP insecticide called phosphamidon was used to control insect pests on conifer trees. Initially the use of this pesticide killed many birds as well as the insect pest, but the Canadians found that by reducing the amount of the chemical used they could control the insects without affecting the bird population. Problems have occurred in particular when OPs have been used to treat seeds and, while this reduces dispersion, animals that eat the seeds can then be poisoned. This has caused the deaths of large numbers of birds in some areas. 

Kusic et al. (1991) have tested the oxime HI-6 in OP pesticide poisoning in 60 patients. HI-6 was administered four times a day as a single i.m. injection of 500 mg with atropine and diazepam treatment. Oxime therapy was started on admission and continued for 2 to 7 days. Most patients were treated with HI-6 and nine patients severely poisoned with quinalphos were treated 2-PAM Cl (1,000 mg four times per day). HI-6 rapidly reactivated human red blood cell AChE inhibited by diethoxy OPs (phorate, pyr-idaphenthion, quinalphos) as well as that inhibited by dichlorvos (a dimethoxy OP). AChE inhibited with other dimethoxy OPs (dimethoate and phosphamidon) was reported to be resistant to HI-6 treatment, whereas reactivation with malathion was slow (reactivation half-time 10 h). Both HI-6 and 2-PAM successfully reactivated AChE in quinalphos-poisoned patients, with HI-6 acting as a faster AChE reactivator than 2-PAM. 

Tarbah FA, Kardel B. Pier S, Temme O, Daldrup T. Acute poisoning with phosphamidon determination of dimethyl phosphate (DMP) as a stable metabolite in a case of organophosphate insecticide intoxication. J Anal Toxicol 2004 28 198-203. 

Tarbah, F. A., Kardel, B., Pier. S Temme, 0 and Daldrup, T. (2004). Acute poisoning with phosphamidon Determination of dimethyl phosphate (DMP) a.s a stable metabolite io a ca.se of organophosphate insecticide poisoning. J. Anal. Toxicol- 28, 198-203. 

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