Analysis of Pesticide Residues in Citrus Oils

Abstract

Citrus oils are widely used in consumer products. Contamination with pesticides is of particular concern because the citrus oils are derived from the outer portion of the fruit. GCxGC-TOFMS provides for analysis for many pesticides in citrus oils with minimal sample preparation. This work shows the ability of this technique to sufficiently separate these pesticides from the citrus oil components, to provide confirmation of identity, and to quantify these residues over several orders of magnitude concentration, reaching as low as part-per-billion levels.

Introduction

Citrus oils are traded internationally and are included in products that are traded internationally. These oils are derived from the outer portion of the fruit, as byproducts in the much more economically important production of citrus juices. And, it is the outside of the fruit that is exposed to the pesticides that are applied to protect the citrus crop and trees. The analysis of citrus oils for pesticides has become increasingly important as pesticides that are acceptable in one market may be banned in another. Even in markets where specific pesticides may be allowed, there are increasing restrictions on the permissible levels of pesticides to which humans or animals may be exposed.