Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi)

Show abstractHide abstract

In food-poisoning outbreaks, the ingestion time of suspect foods has been estimated using the Sartwell method (Hirayama method), the graphical method and maximum likelihood estimation. These methods are based upon the assumption that the incubation period is log-normally distributed. However, these methods may not always be valid because the bias and variability of the estimates are large. We constructed a database from 341 food-poisoning cases in the literature. Using this database, we developed a method to estimate the actual ingestion time based on the period from the ingestion time to the first outbreak, using a multiple linear regression equation. Since only 9.09% of cases showed log-normal distribution, the above three methods would not be valid in most cases. The new method was applicable in all cases. In addition, the values estimated by the new method showed higher correspondence and accuracy than the values estimated by the other methods. Therefore, we consider that the new method is superior to those methods.

View full abstract

Download PDF (547K)

Pesictide residues in 343 samples of domestic rice and 32 samples of imported rice purchased on the Tokyo market from April 1995 to March 2005 were investigated.
Residues of eleven kinds of pesticides (including organophosphorus, organochlorine, carbamate, pyrethroid and organonitrogen pesticides and bromide) were detected at levels between trace and 1 ppm in 47 domestic rice samples. DDVP and bromide residues were detected at levels between 0.01 ppm and 5 ppm in 18 imported rice samples.
For rice samples that were found to containing pesticides, the amounts of pesticide intake were calculated according to the daily intake of rice, and they were compared with the ADI values. Since residual pesticide levels were 17/10,000-2/5 of ADI, all the rice samples were considered to be safe for human consumption.

View full abstract

Register with J-STAGE for free!