Gianfranco Brambilla1 Stefania Paola De Filippis1 Vittorio Esposito2 Gaetano Settimo1
1Environment Department, Istituto Superiore di Sanita`, Rome, Italy 2Agenzia Regionale per la
Prevenzione e Protezione dell’Ambiente Regione Puglia, Taranto, Italy
Research Article
Dioxin Like Compounds Bulk Deposition on Corn
(Zea mais) and Alfa Alfa (Medicago sativa):
Modelled Levels on Derived Silage and Hay and
Their Relevance for Dairy Production
Dioxin-like compounds from regular, occasional or fugitive airborne sources of
emis-sion may fall out on fodders close to be harvested for silage and hay production. In this
way, a prolonged long-term intake of contaminated forages in dairy animals may be
envisaged, able to determine a rise of the background contamination in milk. We
simulated different risk scenarios taking into account the inventoried bulk dry
depo-sitions in rural areas of the aforesaid contaminants, silage and hay biomass production
per hectare, forages regimen in dairy animals, and the congeners carry-over rate (COR)
from forages to milk. Considering atmospheric depositions >10 pg I-TE m
ÿ2day
ÿ1and
accounting for a 30% COR, dairy milk could rise up to the PCDD/F level of 3 pg WHO
1998-TE g
ÿ1fat. The modelling indicates that in rural areas bulk emissions should be
selectively minimised, accounting for the calendar of the different agricultural
prac-tices, because of their potential impact on the fodders. Since environmental factors play
a non-negligible role in food production, a stronger harmonisation between I-TE and
WHO
1998–2005-TE scales with respect to dioxin-like polychlorobiphenyl congeners
inclusion is envisaged. This will allow the prevention of the human indirect exposure
to such contaminants when released in the air.
Keywords: Air deposition; Food management; Forage; Milk; Nutrition Received:October 12, 2011; revised: April 17, 2012; accepted: May 3, 2012 DOI: 10.1002/clen.201100566
1 Introduction
The implementation of monitoring plans for polychlorodibenzodi-oxins and -furans (PCDDs/PCDFs) and dioxin-like polychlorobiphenyls (DL-PCB) contamination, extended also to non-dioxin-like polychloro-biphenyl congeners (NDL-PCBs) for products of animal origin, is more and more highlighting the relevance of some geographically related environmental factors in rural and outdoor animal farming systems. For instance, the quality of top soil has been already investigated, in free range hens production a requisite of 2 pg WHO-TE1998g
ÿ1 dry matter has been suggested, to prevent contamination in eggs from low-density flocks [1]. In Germany, national authorities have already identified a threshold contamination <5 pg I-TE gÿ1dry matter (d.m.) in grazing soils for dairy cows [2, 3]. Correlations have been made between the contamination of sediments in shallow waters and
some mariculture practices, as in the case of farmed fish (www. ymparisto.fi/download.asp?contentid¼27296&lan¼EN, accessed 16 April 2012) [4] and clams [5], as a tool for risk management strategy targeted on reducing the human intake levels below the EU tolerable daily intake of 2 pg WHO1998-TE kg
ÿ1
body weight (b.w.) dayÿ1in the 95% of the general population (http://ec.europa.eu/food/committees/ scientific/out55_en.pdf, accessed 16 April 2012). Previous studies correlated air quality with grass contamination, accounting both for vapour phase and particle bound depositions of contaminants on the epigeal part of the plants. The uptake of airborne PCDDs/Fs by a native pasture sward may represent 86–94% of the overall fodder contamination, with the remaining represented by adhering soil particles, with an equilibrium between air emissions and grass contamination estimated in 2 wk [6, 7]. A recent UK study [8] indicates that the vapour phase from soil looses its relevance in fodder above 40 cm of height. In high stem crops, as in the case of corn, dust fall and particle phase represent the most contributing source of dioxins contamination (http://etdncku.lib.ncku.edu.tw/ ETD-db/ETD-search/view_etd?URN¼etd-0802107-154817, accessed 16 April 2012). A correlation between airborne PCDDs þ PCDFs, mais silage, grass and dairy milk contamination in field conditions have been carried out in 1994–1995 by Schuler et al. [9] over periods of 35– 100 days, within a rural area at 1 km distance from a municipal waste incinerator, in Switzerland. Air depositions ranged from 1.30 to 7.16 pg I-TE mÿ2dayÿ1; corn contamination was 0.03 I-TE pg gÿ1d.m. on September 1994 (lower bound approach) against a monitored air deposition of 4.12 pg I-TE mÿ2dayÿ1 during the same month, just Correspondence: Dr. G. Brambilla, Environment Department, Istituto
Superiore di Sanita`, Viale Regina Elena, 299, I-00161 Rome, Italy E-mail: gianfranco.brambilla@iss.it
Abbreviations: b.w., body weight; COR, carry-over rate; DL-PCB, dioxin-like polychlorobiphenyl; d.m., dry matter; EFSA, European Food Safety Authority; EU, European Union; HRGC/HRMS, high resolution GC/high resolution MS; I-TE, International toxic equivalency; PCDD, polychlorodibenzodioxin; PCDF, polychlorodibenzofuran; PVC, polyvinyl chloride; QA/QC, quality assurance/quality control; TEF, toxic equivalency factor; US-EPA, United States Environmental Protection Agency; WHO, World Health Organisation; WHO1998-TE, World Health Organisation toxicity equivalency according to 1998 scale
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