UNKNOWN LEVELS, UNCERTAIN SOURCES: OR ALL WE KNOW

Transcription

1 UNKNOWN LEVELS, UNCERTAIN SOURCES: OR ALL WE KNOW REGARDING HUMANS AND ORGANOTIN COMPOUNDS Ana C. A. Sousa, M. Ramiro Pastorinho, António J. A. Nogueira, Luís Taborda-Barata, Shin Takahashi, Shinsuke Tanabe

2 ORGANOTIN COMPOUNDS (OTS) Organotins belong to the most widely used organometallic compounds family; More than 8 organotin compounds in use; Estimated annual production: 6, tons. 8% 5% PVC Stabilizers 1% Antifouling biocides Agricultural biocides 76% Catalysts for the production of polyurethanes and silicones EVISA, 29; Mala, 28

3 Butyltins Phenyltins Octyltins ORGANOTIN COMPOUNDS Mono- Di- Tri- Tetra- MBT DBT TBT TeBT MPT DPT TPT TePT MOT DOT TT TeOT PVC stabilizers PVC stabilizers, silicones, Polyurethane foams, FRs Biocides Intermediates

4 Antifouling paints are used to prevent biofouling Ship 6 sea: 15 Kg m -2 of organisms; 4% increase in petrol consumption TRIBUTYLTIN & ANTIFOULING PAINTS TRIBUTYLTIN (TBT) Used as active compound in antifouling paints One of the most toxic xenobiotics ever produced and deliberately introduced into the environment (Goldberg 1986) Highly persistent Extremely toxic to nontarget organisms IMPOSEX Superimposed sex Imposex is the best documented example of endocrine disruption in wildlife.

5 HUMAN EXPOSURE

6 HUMAN HEALTH EFFECTS Endocrine disruption Immunotoxicity Organotin compounds OBESOGENICITY And many, many other nasty tees.

7 EHP, Vol 12 (2) OBESOGENS: Obesogens First described in 26 for OTs (by Grün & Blumberg) TBT activates PPARγ, the master regulator of adipogenesis Refers to those xenobiotics that trough an inappropriate activation of nuclear receptors induce adipocyte differentiation (TBT, BPA, PFOA, ). OBESOGEN HYPOTHESIS: perturbations in metabolic signaling, resulting from exposure to dietary and environmental chemicals, may further exacerbate the effects of imbalances in diet and exercise, resulting in an increased susceptibility to obesity and obesity-related disorders

8 OTs burden in humans Limited information on OTs levels in humans Total No. samples No. Samples No. Publications No. publications Liver Blood Urine Breast milk Placenta J. Sarmento

9 OTs levels - Liver Cornelius De Witt Golden Press. Human liver samples (post-mortem) Sum BTs (ng.g -1 ww) Poland, N=9 Japan, N=4 Denmark, N=18 Kannan & Falandysz, 1999 Takahashi et al, 1999 Nielsen & Strand, 22

10 OTs levels - Blood Cornelius De Witt Golden Press. Values <DL= half DL [Max] ng.ml [BTs] blood MBT DBT TBT Kannan et al, 1999 Whalen et al, 1999 Rüdel & Steinhanses, 21 USA, N=32 USA, N=6 Lo et al, 23 *** Peters, 24 Rantakokko et al, 28 Sousa et al, unpub. [Max] ng.ml [OTs] blood 1.5 MBT DBT TBT MPT DPT TPT 1 MOT DOT.5 Rüdel & Steinhanses, 21 Lo et al, 23 *** Peters, 24 Rantakokko et al, 28 Sousa et al, unpub. Germany, N=3 Germany, N=8 Netherlands, N=91 Finland, N=3 Portugal, N=1

11 OTs levels other matrices Cornelius De Witt Golden Press. Urine samples (Zachariadis & Rosenberg 29, N= 4) [Max] ng Sn.L MBT DBT* TBT MPT* DPT* Breast milk samples (Mino et al, 22; Japan, N=67) [Max] ng.l -1 (as Chlorides) Detected 16% MBT* DBT TBT* TPT* *Values <DL= half DL

12 OTs levels other matrices Placenta (Rantakokko et al, 213, Denmark & Finland, N=28) ng.g -1 fw % Denmark ( percentiles) 37% 37% 31% MBT DBT TBT TPT ng.g -1 fw % Finland ( percentiles) 66% 99% 43% MBT DBT TBT TPT Different exposure sources? % >LOQ

13 ey.com the-scientist.com House dust PEOPLE SPEND 9% OF THEIR TIME INDOORS 2/3 OF THIS TIME IS SPENT AT HOME House dust behaves as a repository and a concentrator of many persistent and toxic chemicals (Mercier et al., 211). [OTs] min-max ng.g -1 dw 4 NY, apts N= Hamburg, apts N= Berlin apts, N=28 EU Parliament, N=15 UK houses (pooled), N=1 5 EU countries, houses, N=1 Fromme et al. 25 Santillo et al 21 Santillo et al 23 Santillo et al 23 Kersten and Reich 23, in Fromme et al. 25 Kannan et al, 21

14 House dust survey - Portugal 27 house dust samples from Aveiro and Coimbra, Portugal (211-12) Quantification of: MBT, DBT, TBT DPT, TPT MOT, DOT

15 OTs house dust - Portugal Total OTs levels highly variable between samples: ng Sn.g -1 dw ng Sn.g -1 dw [OTs] dust Relative contribution of individual organotins to total OTs Relative Contribution (%) Monosubstituted compounds are more abundant MBT DBT TBT MOT DOT Profile of OTs usage in household items

16 OTs house dust - Portugal Extremely high levels of TBT (87 ng Sn.g -1 ) in one house: this concentration is the highest reported so far for house dust. Risk associated with dust ingestion? Adults: ingest 5 mg dust per day Children: ingest 1 mg dust per day daily intake via dust calculations based on average concentrations for the sum of TBT, DBT, TPT and DOT, as suggested by EFSA 36 ng.day ng.day -1 Tolerable Daily Intake (TDI) 1 ng.kg -1 bw.day -1

17 OTs - DIET It is generally assumed that seafood is the main source of organotins, especially TBT and TPT (Rantakokko et al, 26; EC, 23). Most reports on dietary OTs refer to the pre-ban period, TBT levels derived from AF paints were very high. Croatia, Adriatic Coast, [1]* Turkey, Aegean Coast, 29 [2]* Portugal, Coast, 26 [3] Portugal, Ria Aveiro, 25 [4] Italy, Harbor, 25 [5] Italy, Mussel farm, 25 [5] TBT DBT MBT Slovenia, [6] Slovenia, 2-26 [7] Portugal, Coast, 2 [8] Spain, Galicia, 2 [9] Slovenia, Bay of Piran, 2 [1] Portugal, Coast, [11] Italy,Venice lagoon, [12] Italy,Venice lagoon, [13] [Mytillus] ng Sn.g Sousa et al. accepted

18 Duplicate Diet Study - Portugal March May 213 For one week (7 consecutive days) volunteers from Aveiro University kept a duplicate of their diet

19 Duplicate Diet Study - Portugal N= 18 duplicate diet samples ng Sn.g -1 dw MBT DBT TBT DPT TPT MOT DOT EFSA Recommendation (TBT+DBT+TPT+DOT) ng Sn.g -1 dw

20 Conclusion Organotin compounds are ubiquitous; TBT is one of the most toxic xenobiotics ever produced and deliberately introduced into the environment (Goldberg 1986); Imposex: the best example of endocrine disruption in wildlife Innumerous reports on OTs levels and effects in the marine environment In humans, TBT is the OBESOGEN Limited information on the levels of OTs burdens in humans Further research is mandatory.

21 Acknowlegments SAMPLING Inhabitants from Barroca Grande (blood samples); Volunteers from Aveiro and Coimbra, that kindly provided their vacuum cleaner bags. Students & staff from Aveiro University for generously sharing their diet; Sónia D. Coelho (diet samples processing). FUNDING Portuguese Foundation for Science trough program COMPETE Postdoc grants SFRH/BPD/65884/29; SFRH/BPD/26689/26 Projects PEst-C/MAR/LA17/211; Pest-C/SAU/UI79/211 Global COE Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan.

22 Thank you for your attention!