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HUVEC). For all cell types, 40 and 10 �M concentrations wereested during 24 hours and developed by SRB method.

F98226BM had stimulated IC50 > 40 �M in all human cells tested.

oi:10.1016/j.toxlet.2010.03.570

202-035cute systemic toxicological and mutagenic evaluations of aroteolytic fraction from latex of Carica candamarcensis

. Villalba, A. Silva, C. Tagliati, G. Cassali, C. Salas, M. Lopes

Universidade Federal de Minas Gerais, Brazil

ur research group has been characterizing a fraction (P1G10)erived from latex of Carica candamarcensis L. (voucher #15063,niv. La Serena, Chile). The fraction is rich in cysteine-proteases andisplays wound healing activity in vivo on skin and gastric wounds.

n preparation for clinical trials, this study aims to evaluate there-clinical toxicological and mutagenic effects induced by acute1G10 administration. Methods and results: The acute toxicity assayFixed Dose Procedure) was carried out following the guidelinesrovided by the OECD 420, 2001. The lethal dose by p.o. route wasetermined at 2000 mg/kg, while i.p. or i.v. administration yieldedlethal dose of 50 mg/kg. Histopathological examination followingecropsy showed diffuse bleeding on heart, kidneys, bowels andtomach, as probably cause of death. By giving 300 mg/kg (v.o.) ormg/kg (i.p. or i.v.), P1G10 did not cause death or visible changes inody weight, water consumption or food intake, when compared tohe control. The mutagenic evaluation was carried out in vitro byhe Ames test, exposing different Salmonella typhimurium strainsTA97, TA98, TA100, TA102) to 0.1 or 1% P1G10, the correspond-ng positive control or sterile saline, during 24 h. The number ofevertant colonies was significantly different when compared tohe positive control (p < 0.001 ANOVA, Bonferroni post-test), buto significantly different to the negative control. Similarly, the inivo micronucleous test, applied to Swiss mice treated with 5 or0 mg/kg P1G10 did not alter the number of polychromatic ery-hrocytes with micronucleus levels at the bone marrow similar tohe negative control. Conclusion: Considering these results, we cannfer that P1G10 is well tolerated in the studied doses as deter-

ined by different routes of administration and has no mutagenicctivity, clearing the way for future prospective studies.

Financial support: CAPES, CNPq and FAPEMIG.

oi:10.1016/j.toxlet.2010.03.571

202-036enotoxic effect of 3-tesla magnetic resonance image (MRI) inuman lymphocytes

.W. Lee 1, Y.J. Kim 1, M.S. Kim 2, H.D. Woo 1, Y.H. Lee 1, H.W.hung 1

The Graduate School of Public Health, Institute of Health andnvironment, Seoul National University, Republic of Korea,Department of Radiology, National Cancer Center, Republic of Korea

linical use of magnetic resonance imaging (MRI) scanner with

igher magnetic field strengths is increased in recent days. 3-TeslaT) MRI has twice the field strength compared with conventional.5-T MRI units. In this study, the genotoxic potential of high mag-etic field generated during a 3-T clinical MRI scan in human

ymphocyte was investigated by analyzing chromosome aberration

196S (2010) S37–S351 S167

(CA), micronucleus (MN) and single cell gel electrophoresis (Cometassay) in vitro.

Human lymphocytes were exposed to complex MRI field condi-tions (clinical routine brain protocol: 3 channel head coil in GE HDx3.0-T; T2-FSE, T2-FLAIR, T1-SE, DW, DTI, T1-FLAIR sequence) for22, 45, 67 and 89 min, respectively. To rule out the thermal effects,all sample temperatures were maintained at 25 ± 1 ◦C by constanttemperature and humidity equipment.

DNA single-strand breaks were increased significantly afterexposure to 3-T MRI. In the longest exposure time, DNA tail momentwas on the average threefold more than that of control. Frequencyof MN and CA were also increased in an exposure time depen-dent manner. The MN frequency in the lymphocytes exposed for0, 22, 45, 67 and 89 min were 9, 11, 13.5, 16 and 18.5 per 1000cells, respectively. Similarly, the frequency of CA in the lympho-cytes exposed for 0, 67 and 89 min were 1.5, 3.5 and 5.5 per 200cells.

Obtained results suggest that exposure to 3-T MRI induce geno-toxic effects in vitro in human lymphocytes.

doi:10.1016/j.toxlet.2010.03.572

P202-037Genotoxicity of liquid products from pyrolysis of sewagesludge

A. Pillco 1, E. De La Pena 2, M.J. Hazen 3

1 Biochemical Research Institute, University Major of San Andres(UMSA), Saavedra, 2224, La Paz, Bolivia, 2 Laboratory ofEnvironmental Mutagenesis, Environmental Sciences Center, SpanishNational Research Council (CSIC), Serrano 115, 28006 Madrid, Spain,3 Department of Biology, Faculty of Sciences, Autonomous Universityof Madrid, Darwin 2, 28049 Madrid, Spain

Sewage sludge is the waste produced in wastewater treatmentplants. Various thermal treatments such as gasification and pyrol-ysis are currently being studied to valorize this waste. The aim ofthis study was to analyze the potential genotoxicity produced by aliquid product from pyrolysis (LPP) of sewage sludge.

Two short-term bioessays were employed. First LPP was evalu-ated using the Ames Salmonella/microsome mutagenicity test. Theprotocol was followed, using tester strains TA98, TA100, TA102 andTA104 of Salmonella typhimurium. The results showed presence ofmutagenic activity produced by LPP. TA98 and TA100 strains werethe most sensitive.

The second bioessay employed was the in vivo WingSomatic Mutation and Recombination Test (SMART) in Drosophilamelanogaster. The protocol followed used standard cross (ST) andhigh bioactivation cross (HB). 72-h-old larvae trans-heterozygousfor two genetic markers “multiple wing hairs” (mwh) and “flare”(flr3), were treated at different concentrations of the LPP for aperiod of 48 h. The wings of the emerging adult flies were scored forthe presence of spots of mutant cells. For ST, the result showed thatnone of three categories of mutant spots recorded (small, large andtwin) increased significantly by these treatments, independently ofthe dose supplied. In contrast, using HB, LPP showed positive resultsonly for small single spots and weak positive results for total spots.

In conclusion, both alternative methods to animal testing (3Rs)employed demonstrate the existence of a genotoxic risk for LPP,and indicate the need for further research to delineate the exact

mechanisms involved.

Project OTT2007X1317, *MAEC-AECID.

doi:10.1016/j.toxlet.2010.03.573