Measurement uncertainty associated with sample processing of oranges and tomatoes for pesticide residue analysis.

نویسندگان

  • Richard J Fussell
  • Michael T Hetmanski
  • Roy Macarthur
  • Dawn Findlay
  • Frankie Smith
  • Arpad Ambrus
  • Peter Josef Brodesser
چکیده

The homogeneity of analytical samples and the stability of pesticides during the sample processing of oranges and tomatoes were evaluated. The mean concentrations of 14C-labeled chlorpyrifos in analytical portions (subsamples) after processing show that homogeneity is dependent on sample type as well as the processing procedure. The homogeneity of analytical samples of tomatoes processed cryogenically was much better than those processed at ambient temperature. For tomatoes, the minimum analytical portion masses required for between-analytical portion variation of < 0.3 Ho were 110 and 5 g for processing at ambient and cryogenic temperatures, respectively. Results for orange showed that analytical portion sizes of 5 g provided sufficient homogeneity from both sample processing procedures. Assessments of pesticide stability demonstrated that most were relatively stable during processing at either ambient or cryogenic temperatures. However, some pesticides, including dichlofluanid, chlorothalonil, tolylfluanid, and dicloran, appeared to suffer much greater losses (>20%) during processing at ambient temperature. For these analytes, loss is interpreted as chemical degradation.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The Effects of House Cooking Process on Residue Concentrations of 41 Multi-Class Pesticides in Rice

In current study, the effects of Iranian rice cooking method (Kateh) on residue levels of 41 pesticides were investigated. The pesticides were selected according to Iranian National Standards Organization (INSO) regulations and covered 18 permitted and 23 banned pesticides belonging to different chemical classes such as organophosphate, triazole, and carbamate. A 250 g portion of rice sample wa...

متن کامل

The Effects of House Cooking Process on Residue Concentrations of 41 Multi-Class Pesticides in Rice

In current study, the effects of Iranian rice cooking method (Kateh) on residue levels of 41 pesticides were investigated. The pesticides were selected according to Iranian National Standards Organization (INSO) regulations and covered 18 permitted and 23 banned pesticides belonging to different chemical classes such as organophosphate, triazole, and carbamate. A 250 g portion of rice sample wa...

متن کامل

Pesticide Exposure and Head and Neck Cancers: A Case-Control Study in an Agricultural Region

Introduction: Causes of head and neck cancers (HNCs) are multifactorial, and few studies have investigated the association between chemical exposure and HNCs. The objective of this study was to investigate associations between HNCs, agricultural occupations, and pesticide exposure. The potential for the accumulation of pesticides in the adipose tissue of patients was also investigated.   Materi...

متن کامل

[Investigation of pesticide residues in foods distributed in Kitakyushu City].

We investigated 160 kinds of pesticide residues in 715 samples of 116 kinds of foods distributed in Kitakyushu city. Sixty kinds of pesticides were detected in 55 kinds of foods (204 samples) in the range of 0.002-22 mg/kg. Five kinds of pesticides in 7 samples violated the residue standards and the indication of "unused". The detection ratios of unregulated pesticide in domestic and imported f...

متن کامل

A comparative study of allowable pesticide residue levels on produce in the United States

BACKGROUND The U.S. imports a substantial and increasing portion of its fruits and vegetables. The U.S. Food and Drug Administration currently inspects less than one percent of import shipments. While countries exporting to the U.S. are expected to comply with U.S. tolerances, including allowable pesticide residue levels, there is a low rate of import inspections and few other incentives for co...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of agricultural and food chemistry

دوره 55 4  شماره 

صفحات  -

تاریخ انتشار 2007