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Acetamiprid belongs to a new class of insecticides called neonicotinoids, which have different effects from other insecticides. Neonicotinoids act as selective agonists at the nicotinic acetylcholine receptors, therefore their toxicity is higher to insect pests than to humans. Cases of acetamiprid poisoning are still rare, because neonicotinoids have been released in the market only within the last decade. We experienced a case of acute acetamiprid poisoning and measured the blood concentration of acetamiprid. A 79-year-old man had ingested acetamiprid and got medical attention two hours after ingestion. On arrival, he had consciousness disturbance (GCS-8), hypotension, nausea, vomiting and hyperglycemia, but had no constricted pupils nor mucous supersecretion which are characteristic in organophosphate poisoning. Gastric lavage was performed and activated charcoal and laxative were administered. Paroxysmal atrial fibrillation persisted until 11 hours after ingestion. The next day, his symptoms with regards to the effects of acetamiprid improved and he was discharged from the hospital without complication. Blood concentration of acetamiprid on arrival, approximately 2 hours after the ingestion, was 21.1 microg/ml.

The serum drug concentrations were measured by HPLC or GC/MS in 15 patients of acute fenitrothion (MEP), an organophosphorus insecticide, intoxication. There was no fatal case. The patients were admitted 0.5 approximately 12 hours after the ingestion of 5 approximately 50g MEP. The range of serum MEP concentrations were from undetectable level (< 0.01 microg/mL) to 9.73 microg/mL. Toxic symptoms were correlated with the serum MEP levels. About < 7 microg/mL of the serum MEP levels associated with mild cases and about > 7 microg/mL associated with serious cases. The elimination curves in mild cases were successfully simulated by the one-compartment model and the elimination half-lives (T1/2) were 9.9 +/- 7.7hr (mean +/- S.D.). The serum MEP concentrations declined below the detectable level in 48hr. The elimination curves in two serious cases were successfully simulated by the two-compartment model. The T1/2 in the alpha phase were 5.3hr and 6.7hr (under the direct hemoperfusion), and the T1/2 in the beta phase were 35hr and 52hr. The serum MEP concentrations declined below the detectable level in 300hr.

Carbaryl and propanil in human serum and urine were determined by automatic on-line column enrichment technique followed by reversed-phase HPLC with photometric detection. Human serum was filtered through a membrane filter (0.45 micron pore size) and an aliquot of 0.1 ml of the filtrate was diluted with water up to 1 ml. The solution of 0.8 ml was directly injected to automatic HPLC without any preparation. Urine was incubated with beta-glucuronidase/arylsulfate for 16 hours at 37 degrees C. The resultant solution was then filtered through a membrane filter and the filtrate was analyzed by the similar manner as serum. Carbaryl and propanil in the sample solution were concentrated on a pre-conditioned ODS mini-column. After washing the mini-column with 5% methanol, they were separated by an ODS analytical column (Cosmosil 5 C18-MS, 250 x 4.6 mm i.d.) with acetonitrile/water (30:70, v/v) eluent and detected with a UV detector. Carbaryl and propanil in serum were detected at 220 and 210 nm, respectively. On the other hand, in order to separate from blank peaks, carbaryl and propanil in urine were detected at 290 and 260 nm, respectively. The presented HPLC method requires neither manual procedure of solid-phase nor liquid-liquid extraction. Calibration curves for carbaryl and propanil were linear over the range of 5 ng/ml-2 micrograms/ml in both serum and urine. Real serum (ng/ml level) and urine (microgram/ml level) samples were analyzed by the presented HPLC method. Effect of seventeen pesticides on the determination of carbaryl and propanil were investigated. All pesticides did not interfere with the determination except for thiuram.

Pest control operators usually spray pesticides in small areas such as a kitchen in a restaurant and are exposed to various pesticides, especially those of the organophosphorus (OP) type. In order to evaluate their occupational exposure to OP pesticides during the work, OP pesticides in blood and alkyl phosphate metabolites in urine of these operators were analyzed and the relationship between pesticide exposure and analytical results were studied. OP pesticides in blood were analyzed by gas chromatography with flame photometric detector (FPD-GC) after separation of phospholipid in blood with silicagel column chromatography. OP pesticides were not detected in any blood samples (the limit of detection was 1 ng/ml). Dimethylphosphate (DMP) and dimethylthiophosphate (DMTP), being urinary metabolites of OP pesticides, were analyzed by FPD-GC after benzyl derivatization. This method eliminated interfering peaks in gas chromatograms. The ratio of two isomeric derivatives of DMTP was found to be constant. Both DMP and DMTP of the exposed group were significantly higher than those of the non-exposed group, DMP being higher than DMTP. The ratio of DMP to DMTP in the fenitrothion-dichlorvos-exposed group was significantly higher than that in the fenitrothion-exposed group. It was considered that the ratio might reflect a result of pesticide exposure. The urinary metabolites of OP pesticides tended to become lower with the lapse of time since the last exposure. However, small amounts were detected in a few samples even 5 days after the last exposure.