LIBRO-CONGRESO-CITRUS

S20
of satsuma, however, (even some people just eat one) induces “Shang huo”. This reaction is an itching or
burning sensation in the lips, mouth, ear canal, and/or pharynx. Sometimes other reactions can be triggered
in the eyes, nose, and skin. “Shang huo” make people afraid of eating satsuma and have negative impact on
the citrus planting efficiency. Litchi and longan fruit also produce this kind of effect. This study was focused
on the analysis of the mechanism of “Shang huo” by a case-control study. 200 volunteers participated in
the project. In the first night, from 7 pm to 9 pm, male volunteers ate more than 1.5 Kg satsuma at a time,
and female volunteers ate 1 Kg. This consumption was 2-3 times above normal consumption. Individual
reactions were carefully observed and recorded for continuous 3 days. Statistically significant differences
were found.
S20P07
Dissipation curves of cypermethrin in whole fruit and mandarin pulp in Argentina
Kulczycki Waskowicz C. 1 , Sosa A. 1 , Beldoménico H. 2 , García S. 2 , and Repetti M.R. 2
1National Institute of Agricultural Technology, Concordia Agricultural Experiment Station (INTA, EEA Concordia), Pesticides Residues
Plant Protection, Argentina; and 2 School of Chemical Engineering, Santa Fe (UNL), Central Laboratory, Pesticide Division, Argentina.
ckulczycki@correo.inta.gov.ar
Cypermethrin is a pyrethroid insecticide used for pest control in several crops. The objective was to determine
a degradation curve of cypermethrin in whole fruit and mandarin pulp. The assay was performed in a plot
of satsuma mandarin located at INTA’s Agricultural Experiment Station in Concordia during summer 2011.
The treatment used 25% of cypermethrin at a dose of 60 cm3/hl commercial formulation. The treatment
was performed with a high volume spray under Good Agricultural Practice. Volume applied was 2916 l/
ha. Pesticide degradation in fruit was studied for a 61-day period since insecticide application and included
periodic samplings. The residue determinations were performed by gas chromatography with ECD detector.
The quantification limit was 6 µg/kg and the detection limit 3 µg/kg. Fruit diameter and internal quality was
also determined: juice percentage and maturity rate (ºBrix, % titratable acidity). The first elimination phase
was fast, from an initial deposit of 0.51 mg/kg to 0.15 mg/kg after 21 days. The second elimination phase was
slower reaching at the end of the experiment levels of 0.06 mg/kg. No residues were detected in pulp. Fruit
diameter remained constant throughout the assay; therefore, the dilution factor due to growth of plant tissue
was not considered. In whole fruit, even though residue levels of cypermethrin were low, presence at the end
of the assay showed great persistence.
S20P08
Dissipation and residue of forchlorfenuron in citrus fruits
Chen W. J. 1 , Su X. S. 2 , Zhao Q. Y. 1 , and Jiao B. N. 1
1Citrus Research Institute, Chinese Academy of Agricultural Sciences, China; and 2Chemistry and Chemical Engineering, Southwest
University, China. suxuesu@163.com
The dissipation and residue of forchlorfenuron in citrus fruits under field conditions were studied. The
field trial was conducted in Guangzhou, Zhejiang and Hainan provinces, China. An analytical method using
QuEChERS cleanup and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/
MS) was successfully applied to analyze forchlorfenuron in citrus fruits. The recoveries of forchlorfenuron
were found in the range of 82.8%-95.5% at three spike levels, with relative standard deviations of 2.1-%-
8.0-%. The results showed that the degradation rate of forchlorfenuron in citrus fruits followed the firstorder
kinetics equation C=A∙eBt.The half-live of forchlorfenuron were 15.8-23.0 days. The degradation rate
of forchlorfenuron in citrus at 42 days (2010) and 52 days (2011) were 82.4-86.4% and 80.6-88.3%. The
results of final residual trial revealed that when the citrus plants were sprayed at 1-2 times successively at the
concentration of 20 mg ai/L and 30 mg ai/L, the residues in pulp of citrus fruits were lower than 0.003 mg/kg
and most of the residues were concentrated in the peel. The results could give a reference for MRL setting of
forchlorfenuron in citrus fruits in China.
348 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012