§ The Countess of Marasked Her Majesty's Government:
Further to the Written Answer by the Lord Bach on 1 November (WA 8), what are the short-term health effects associated with the ingestion of pyridostigmine bromide; and how they differ from those of exposure to organophosphates; and [HL4789]
Whether the combined ingestion of repeated doses of pyridostigmine bromide (PB) and dermal exposure to, inhalation or ingestion of organophosphate pesticides (OPs) would have any different human health effect from ingestion of PB alone or exposure to OPs alone; and [HL4791]
Further to the Written Answer by the Lord Bach on 1 November (WA 8), whether the fact that no case of acute organophosphate poisoning was recorded in United Kingdom troops in the Gulf in 1990–91 indicates that no cases occurred at that time, in the light of the statements in Health and Safety Executive guidance note MS17 concerning the difficulty of diagnosis. [HL4828]
§ Lord BachThe main side effects of pyridostigmine bromide (PB) may include: nausea, vomiting, increased salivation, diarrhoea and abdominal cramps. PB acts by temporarily and incompletely blocking the enzyme acetylcholinesterase. Thus, any side effects are temporary. The acute effects of organophosphate (OP) pesticides, in sufficient dose, may include giddiness, anxiety, restlessness, headache, confusion, failure to concentrate, respiratory depression, excesive salivation, sweating, miosis, loss of bladder control, bradycardia, hypertension, tachycardia, tremor and paralysis. The severity and magnitude of these effects depends on the 195WA particular organosphosphate chemical involved and the route and extent of exposure.
Although the precise mechanisms are different, both PB and OP pesticides in sufficiently high dose are inhibitors of the enzyme acetylcholinesterase. The effects of combinations of the substances in humans are unknown and are diffficult to study.
The Health and Safety Executive guidance note MS17 cautions that OP pesticide-induced symptoms associated with the central nervous system (giddiness, anxiety, retlessness, headache, confusion, failure to concentrate, respiratory depression) may not be easily detected. The primary risk from exposure to OP pesticides used in the 1990–91 Gulf conflict would have been to environmental health personnel applying the pesticides. The Armed Forces and service medical personnel on deployment would be likely to be more atttuned to symptoms of ill health, and any possible link to handling of pesticides than might be the case in other situations.