SEPTEMBER 2013: REPORT ON BAITS COLLECTED AT SEVERAL WATER HOLES WITHIN LAKE NAKURU NATIONAL PARK

By DR. E. Ndambiri.

Background Information

Six samples were collected on 15/9/2013 by rangers on patrol at several water holes in Lake Nakuru National Park. These included purple crystals wrapped with a polythene paper, black liquid in can labeled KEROL, White powder in two different packages; one wrapped in aluminium foil and another wrapped in a polythene paper and inserted in a plastic can labeled CERESTAMINE, sliced bread which appeared to have been laced with black liquid and purple crystals and lastly pieces of pineapples which appeared to have been laced with white powder. These were suspected to have been used as baits targeting rhinos. They were taken for analysis at Government Chemist on 17/9/2013.

Photo showing pieces of pineapples and slices of bread laced with poison(s).

Laboratory Findings

The laboratory was requested to identify the unknown chemicals and also determine whether the sliced bread or/and pineapples were laced with any of the chemical(s). Analytical report was issued vide Certificate of Analysis Ref. No. P/Chem/Vol.1/12-13/ (34) dated 1/10/2013 which identified as follows;

Serial No. Sample Description Analytical Result(Identifications) 1. Purple Crystals Furadan (Carbofuran) 2. Black Liquid Kerol (Disinfectant) 3. White Powder Methomyl Lannate (Insecticide) 4. White Powder Methomyl Lannate (Insecticide) 5. Bread Slices Sliced bread laced with Kerol(Disinfectant) 6. Pineapple Slices Pineapples laced with Methomyl lannate (Insecticide)

Result Interpretation/ Insight.

Bread and pineapples were used as carriers of the chemicals which were meant to be consumed by the target animals. Upon being laced with these chemicals they become effective baits to the targeted animals. Kerol (disinfectant) has strong characteristic oduor which is thought to possibly attract the target animals to where the bait is. Furadan and Methomyl Lannate are examples of CARBAMATE insecticides.

Carbamate insecticides inhibit cholinesterase at nerve junctions with less durable bond than Organophosphates. Clinical signs include hypersalivation, gastrointestinal hypermotility (diarrhea), abdominal cramping, vomiting, sweating, dyspnea, cyanosis, miosis, muscle fasciculations and in extreme cases tetany followed by weakness and paralysis and convulsions. Death results due to hypoxia(less oxygen into the lungs caused by bronchoconstriction).

Diagnosis can be through history of exposure to a particular carbamate and response to atropine therapy. If no such history but cholinergic signs suggest carbamate or organophosphate poisoning, cholinesterase levels can be determined in serum, red blood cells or brain tissue. Screening gastrointestinal contents for these insecticides may be helpful.

Treatment of Carbamate poisoning is similar to that of organophosphate poisoning. Atropine sulfate injections readily reverse the effects of inhibition. Note that also Alloxine (cholinesterase-reactivating compound) greatly improves recovery from carbamate poisoning if given along with atropine.