Penetration Studies of Propoxur and Phoxim from Eggshell into Whole Egg after Experimental Exposure and Application in Henhouses

Abstract

The penetration of propoxur and phoxim from eggshell into whole egg was investigated in vitro by spraying eggs directly and in vivo after application of the compounds in henhouses. Although mean concentrations of the compounds on eggshells were up to 23000 microg kg(-1), mean residue concentrations in whole eggs were far below the current maximum residue levels (50 microg kg(-1) for propoxur and 60 microg kg(-1) for phoxim). These results provide the first evidence that propoxur and phoxim do not penetrate from eggshell into whole egg under experimental and field conditions. Subsequently, residue carry-over after egg cracking in households and during a worst-case situation in an egg-cracking plant was investigated. However, when eggs were cracked manually, a negligible contamination of whole egg values occurred. If, in an automated process, eggshells accidentally come into close contact with whole egg, very high residue levels of propoxur and phoxim may be generated time dependently. These results suggest that eggshell contact with whole egg during egg cracking must be avoided to prevent pesticide carry-over.

Analytical methods applied to the determination of pesticide residues in foods of animal origin. A review of the past two decades

“…Insecticides and acaricides are used in henhouses to control poultry ectoparasites such as red mite; chickens and laying hens can then be accidentally exposed to these chemicals [44]. Poultry can also be contaminated by feeding on plant materials that have been treated with pesticides during the growing and/or storage stages.…”

“…Consequently, chickens and hens accumulate residues in muscles, fat, and liver [4,29,37]. Pesticide residues can also be detected in eggs [44][45][46], even long after the chemicals have been eliminated from the other tissues of the laying hens [47]. In some countries poultry and eggs can be a major source of human exposure to pesticide contamination [4].…”

Simultaneous determination of phoxim and its photo-transformation metabolite residues in eggs using liquid chromatography coupled with electrospray ionization tandem mass spectrometry

“…Phoxim, one of the most extensively utilized of the OPs, is frequently employed in the control of a variety of ectoparasites in pigs and sheep, via dipping, spraying, and/or pour-on applications [3]. In the poultry house, the manufacturers of phoxim recommend spraying all crevices with solutions containing 0.2% phoxim, and also recommend that the hens be prevented from coming into direct contact with the spray solutions [4]. After spraying, the active compounds may be absorbed through the skin or inhaled by the hens and subsequently deposited in the body, including the ovaries.…”

“…After spraying, the active compounds may be absorbed through the skin or inhaled by the hens and subsequently deposited in the body, including the ovaries. Furthermore, it also appears possible that the compounds could be transferred directly from dust particles or hen feathers to freshly laid eggs [4]. The toxic effects associated with phoxim exposure are related to its irreversible inhibition of the acetylcholinesterase enzyme, which exerts acute effects in humans and/or animals [5].…”

“…Residue methods involving high-performance liquid chromatography (UV and/or DAD) detectors have been previously reported for the detection of phoxim in Crucian carp [11], in eggs [3,4], in wheat [12], and in water [13,14]. Additionally, methods using polyclonal antibody [15] or chemometrics [16] have also been previously described.…”