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Physicochemical characteristics and bronchial epithelial cell cytotoxicity of Folpan 80 WG(R) and Myco 500(R), two commercial forms of folpet.

Canal-Raffin M, L'azou B, Martinez B, Sellier E, Fawaz F, Robinson P, Ohayon-Courtès C, Baldi I, Cambar J, Molimard M, Moore N, Brochard P - Part Fibre Toxicol (2007)

Bottom Line: Folpet degradation products and vehicles of Folpan 80 WG(R) did not show any cytotoxicity at tested concentrations.At non-cytotoxic and subtoxic concentrations, Folpan 80 WG(R) was found to increase DCFH-DA fluorescence.This work confirms the need for further studies on the effect of environmental pesticides on the respiratory system.

View Article: PubMed Central - HTML - PubMed

Affiliation: Laboratoire Santé-Travail-Environnement (EA 3672), Université Bordeaux 2, Bordeaux, France. mireille.canal@pharmaco.u-bordeaux2.fr.

ABSTRACT

Background: Pesticides, in particular folpet, have been found in rural and urban air in France in the past few years. Folpet is a contact fungicide and has been widely used for the past 50 years in vineyards in France. Slightly water-soluble and mostly present as particles in the environment, it has been measured at average concentration of 40.1 mug/m3 during its spraying, 0.16-1.2 mug/m3 in rural air and around 0.01 mug/m3 in urban air, potentially exposing both the workers and the general population. However, no study on its penetration by inhalation and on its respiratory toxicity has been published. The objective of this study was to determine the physicochemical characteristics of folpet particles (morphology, granulometry, stability) in its commercial forms under their typical application conditions. Moreover, the cytotoxic effect of these particles and the generation of reactive oxygen species were assessed in vitro on respiratory cells.

Results: Granulometry of two commercial forms of folpet (Folpan 80WG(R) and Myco 500(R)) under their typical application conditions showed that the majority of the particles (>75%) had a size under 5 mum, and therefore could be inhaled by humans. These particles were relatively stable over time: more than 75% of folpet remained in the particle suspension after 30 days under the typical application conditions. The inhibitory concentration (IC50) on human bronchial epithelial cells (16HBE14o-) was found to be between 2.89 and 5.11 mug/cm2 for folpet commercial products after 24 h of exposure. Folpet degradation products and vehicles of Folpan 80 WG(R) did not show any cytotoxicity at tested concentrations. At non-cytotoxic and subtoxic concentrations, Folpan 80 WG(R) was found to increase DCFH-DA fluorescence.

Conclusion: These results show that the particles of commercial forms of folpet are relatively stable over time. Particles could be easily inhaled by humans, could reach the conducting airways and are cytotoxic to respiratory cells in vitro. Folpet particles may mediate its toxicity directly or indirectly through ROS-mediated alterations. These data constitute the first step towards the risk assessment of folpet particles by inhalation for human health. This work confirms the need for further studies on the effect of environmental pesticides on the respiratory system.

No MeSH data available.


Related in: MedlinePlus

Stability of folpet in aqueous suspension over time. Total folpet concentration of Folpan 80WG® and Myco 500® suspended at 1 g/l of folpet in water (usual working concentration) was measured by HPLC-UV/DAD over 30 days and expressed as the proportion of the folpet concentration at day zero (%). Mean total folpet concentration (n = 5, ± se) is represented.
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Figure 5: Stability of folpet in aqueous suspension over time. Total folpet concentration of Folpan 80WG® and Myco 500® suspended at 1 g/l of folpet in water (usual working concentration) was measured by HPLC-UV/DAD over 30 days and expressed as the proportion of the folpet concentration at day zero (%). Mean total folpet concentration (n = 5, ± se) is represented.

Mentions: The chemical stability of folpet particles in Folpan 80WG® and Myco 500® was analysed under their typical application conditions: 1 g/l aqueous suspension at ambient temperature with a daylight/dark cycle over a period of 30 days (Fig. 5). At day zero there was no statistical difference (Student's t test, p = 0.6304) in total folpet concentration between Folpan 80WG® (0.964 ± 0.03 g/l) and Myco 500® (0.982 ± 0.02 g/l). At 30 days there remained 78.68% (± 2.32) of folpet in the Folpan 80WG® sample and 75.47% (± 2.12) in the Myco 500® sample, which was found not to be statistically different (Student's t test, p = 0.3374). Over the first 21 days, folpet degradation was more rapid than the days that followed and folpet in Folpan 80WG® degraded more rapidly than in Myco 500® (Fig. 5). The pH of the particle suspension started between 7.8 and 7.7 at day zero and decreased slowly to reach a value of 6.8 and 6.5 for Folpan 80WG® and Myco 500® respectively at day 30 (Table 2).


Physicochemical characteristics and bronchial epithelial cell cytotoxicity of Folpan 80 WG(R) and Myco 500(R), two commercial forms of folpet.

Canal-Raffin M, L'azou B, Martinez B, Sellier E, Fawaz F, Robinson P, Ohayon-Courtès C, Baldi I, Cambar J, Molimard M, Moore N, Brochard P - Part Fibre Toxicol (2007)

Stability of folpet in aqueous suspension over time. Total folpet concentration of Folpan 80WG® and Myco 500® suspended at 1 g/l of folpet in water (usual working concentration) was measured by HPLC-UV/DAD over 30 days and expressed as the proportion of the folpet concentration at day zero (%). Mean total folpet concentration (n = 5, ± se) is represented.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2211752&req=5

Figure 5: Stability of folpet in aqueous suspension over time. Total folpet concentration of Folpan 80WG® and Myco 500® suspended at 1 g/l of folpet in water (usual working concentration) was measured by HPLC-UV/DAD over 30 days and expressed as the proportion of the folpet concentration at day zero (%). Mean total folpet concentration (n = 5, ± se) is represented.
Mentions: The chemical stability of folpet particles in Folpan 80WG® and Myco 500® was analysed under their typical application conditions: 1 g/l aqueous suspension at ambient temperature with a daylight/dark cycle over a period of 30 days (Fig. 5). At day zero there was no statistical difference (Student's t test, p = 0.6304) in total folpet concentration between Folpan 80WG® (0.964 ± 0.03 g/l) and Myco 500® (0.982 ± 0.02 g/l). At 30 days there remained 78.68% (± 2.32) of folpet in the Folpan 80WG® sample and 75.47% (± 2.12) in the Myco 500® sample, which was found not to be statistically different (Student's t test, p = 0.3374). Over the first 21 days, folpet degradation was more rapid than the days that followed and folpet in Folpan 80WG® degraded more rapidly than in Myco 500® (Fig. 5). The pH of the particle suspension started between 7.8 and 7.7 at day zero and decreased slowly to reach a value of 6.8 and 6.5 for Folpan 80WG® and Myco 500® respectively at day 30 (Table 2).

Bottom Line: Folpet degradation products and vehicles of Folpan 80 WG(R) did not show any cytotoxicity at tested concentrations.At non-cytotoxic and subtoxic concentrations, Folpan 80 WG(R) was found to increase DCFH-DA fluorescence.This work confirms the need for further studies on the effect of environmental pesticides on the respiratory system.

View Article: PubMed Central - HTML - PubMed

Affiliation: Laboratoire Santé-Travail-Environnement (EA 3672), Université Bordeaux 2, Bordeaux, France. mireille.canal@pharmaco.u-bordeaux2.fr.

ABSTRACT

Background: Pesticides, in particular folpet, have been found in rural and urban air in France in the past few years. Folpet is a contact fungicide and has been widely used for the past 50 years in vineyards in France. Slightly water-soluble and mostly present as particles in the environment, it has been measured at average concentration of 40.1 mug/m3 during its spraying, 0.16-1.2 mug/m3 in rural air and around 0.01 mug/m3 in urban air, potentially exposing both the workers and the general population. However, no study on its penetration by inhalation and on its respiratory toxicity has been published. The objective of this study was to determine the physicochemical characteristics of folpet particles (morphology, granulometry, stability) in its commercial forms under their typical application conditions. Moreover, the cytotoxic effect of these particles and the generation of reactive oxygen species were assessed in vitro on respiratory cells.

Results: Granulometry of two commercial forms of folpet (Folpan 80WG(R) and Myco 500(R)) under their typical application conditions showed that the majority of the particles (>75%) had a size under 5 mum, and therefore could be inhaled by humans. These particles were relatively stable over time: more than 75% of folpet remained in the particle suspension after 30 days under the typical application conditions. The inhibitory concentration (IC50) on human bronchial epithelial cells (16HBE14o-) was found to be between 2.89 and 5.11 mug/cm2 for folpet commercial products after 24 h of exposure. Folpet degradation products and vehicles of Folpan 80 WG(R) did not show any cytotoxicity at tested concentrations. At non-cytotoxic and subtoxic concentrations, Folpan 80 WG(R) was found to increase DCFH-DA fluorescence.

Conclusion: These results show that the particles of commercial forms of folpet are relatively stable over time. Particles could be easily inhaled by humans, could reach the conducting airways and are cytotoxic to respiratory cells in vitro. Folpet particles may mediate its toxicity directly or indirectly through ROS-mediated alterations. These data constitute the first step towards the risk assessment of folpet particles by inhalation for human health. This work confirms the need for further studies on the effect of environmental pesticides on the respiratory system.

No MeSH data available.


Related in: MedlinePlus