Heavy Metals in Soil and Salad in the Proximity of Historical Ferroalloy Emission

Roberta Ferri, Filippo Donna, Donald R. Smith, Stefano Guazzetti, Annalisa Zacco, Luigi Rizzo, Elza Bontempi, Neil J. Zimmerman, Roberto G. Lucchini

Department of Experimental and Applied Medicine, University of Brescia, Brescia, Italy.
INSTM and Chemistry for Technologies Laboratory, University of Brescia, Brescia, Italy.
Microbiology and Environmental Toxicology, University of California, Santa Cruz, USA.
Public Health Service, Reggio Emilia, Italy.
School of Health Sciences, Purdue University, West Lafayette, USA.

DOI: 10.4236/jep.2012.35047                

Abstract

Emissions of manganese (Mn), lead (Pb), iron (Fe), zinc (Zn), copper (Cu) from ferro-alloy operations has taken place in Valcamonica, a pre-Alp valley in the province of Brescia, Italy, for about a century until 2001. Metal concentrations were measured in the soil of local home gardens and in the cultivated vegetables. Soil analysis was carried out using a portable X-Ray Fluorescence (XRF) spectrometer in both surface soil and at 10 cm depth. A subset of soil samples (n = 23) additionally was analysed using the modified BCR sequential extraction method and ICP-OES for intercalibration with XRF (XRF Mn = 1.33 * total OES Mn – 71.8; R = 0.830, p < 0.0001). Samples of salads (Lactuca sativa and Chichorium spp.) were analyzed with a Total Reflection X-Ray Fluorescence (TXRF) technique. Vegetable and soil metal measurements were performed in 59 home gardens of Valcamonica, and compared with 23 gardens from the Garda Lake reference area. Results indicate significantly higher levels of soil Mn (median 986 ppm vs 416 ppm), Pb (median 46.1 ppm vs 30.2 ppm), Fe (median 19,800 ppm vs 13,100 ppm) in the Valcamonica compared to the reference area. Surface soil levels of all metals were significantly higher in surface soil compared to deeper soil, consistent with atmospheric deposition. Significantly higher levels of metals were shown also in lettuce from Valcamonica for Mn (median 53.6 ppm vs 30.2) and Fe (median 153 vs 118). Metals in Chichorium spp. did not differ between the two areas. Surface soil metal levels declined with increasing distance from the closest ferroalloy plant, consistent with plant emissions as the source of elevated soil metal levels. A correlation between Mn concentrations in soil and lettuce was also observed. These data show that historic ferroalloy plant activity, which ended nearly a decade before this study, has contributed to the persistence of increased Mn levels in locally grown vegetables. Further research is needed to assess whether this increase can lead to adverse effects in humans and plants especially for Mn, an essential element that can be toxic in humans when exceeding the homeostatic ranges.

Keywords

Heavy Metals; Ferroalloy Plant; Soil; Vegetables; XRF; ICP-OES

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	M. Muller and M. Anke, “Distribution of Cadmium in the Food Chain (Soil-Plant-Human) of a Cadmium Exposed Area and the Health Risks of the General Population,” Science of the Total Environment, Vol. 156, No. 2, 1994, pp. 151-159. doi:10.1016/0048-9697(94)90352-2
[2]	H. T. Davis, C. M. Aelion, S. McDermott and A. B. Lawson, “Identifying Natural and Anthropogenic Sources of Metals in Urban and Rural Soils Using GIS-Based Data, PCA, and Spatial Interpolation,” Environmental Pollution, Vol. 157, No. 8-9, 2009, pp. 2378-2385. doi:10.1016/j.envpol.2009.03.021
[3]	C. M. Aelion, H. T. Davis, S. McDermott and A. B. Lawson, “Metal Concentrations in Rural Topsoil in South Carolina: Potential for Human Health Impact,” Science of the Total Environment, Vol. 402, No. 2-3, 2008, pp. 149-156. doi:10.1016/j.scitotenv.2008.04.043
[4]	Y. Liu, S. McDermott, A. Lawson and C. M. Aelion, “The Relationship between Mental Retardation and Developmental Delays in Children and the Levels of Arsenic, Mercury and Lead in Soil Samples Taken near Their Mother’s Residence during Pregnancy,” International Journal of Hygiene and Environmental Health, Vol. 213, No. 2, 2010, pp. 116-123. doi:10.1016/j.ijheh.2009.12.004
[5]	S. M. Reichman, “The Responses of Plants to Metal Toxicity: A Review Focusing on Copper, Manganese and Zinc,” Australian Minerals & Energy Environment Foundation, Published as Occasional Paper No. 14, 2010. http://www.plantstress.com/Articles/toxicity_i/Metal_toxicity.pdf.
[6]	Y. J. Cui, Y.-G. Zhu, R. H. Zhai, Y. Z. Huang, Y. Qiu and J. Z. Liang, “Exposure to Metal Mixtures and Human Health Impacts in a Contaminated Area in Nanning, China,” Environment International, Vol. 31, No. 6, 2005, pp. 784790. doi:10.1016/j.envint.2005.05.025
[7]	M. Intawongse and J. R. Dean, “Uptake of Heavy Metals by Vegetable Plants Grown on Contaminated Soil and Their Bioavailability in the Human Gastrointestinal Tract,” Food Additives & Contaminants, Vol. 23, No. 1, 2006, pp. 36-48. doi:10.1080/02652030500387554
[8]	M. J. Mc Laughlin, D. R. Parker and J. M. Clarke, “Metals and Micronutrients-Food Safety Issues,” Field Crops Research, Vol. 60, No. 1-2, 1999, pp. 143-163. doi:10.1016/S0378-4290(98)00137-3
[9]	S. Clemens, M. G. Palmgren and U. Kramer, “A Long Way Ahead: Understanding and Engineering Plant Metal Accumulation,” Trends in Plant Science, Vol. 7, No. 7, 2009, pp. 309-315. doi:10.1016/S1360-1385(02)02295-1
[10]	A. R. Memon and P. Schroder, “Metal Accumulation in Plants and Its Implication in Phytoremediation,” Environmental Science Pollution, Vol. 16, No. 2, 2009, pp. 162-175.
[11]	D. R. Sauerbeck, “Uptake and Availability of Heavy Metals,” Water Air Soil Pollution, Vol. 57-58, No. 1, 1991, pp. 227-237. doi:10.1007/BF00282886
[12]	P. S. Hooda, “Plant Availability of Heavy Metals in Soils Previously Amended with Heavy Applications of Sewage Sludge,” Journal of the Science of Food Agriculture, Vol. 73, No. 4, 1997, pp. 446-454. doi:10.1002/(SICI)1097-0010(199704)73:4<446::AID-JSFA749>3.0.CO;2-2
[13]	G. P. Cobb, K. Sands, M. Waters, B. G. Wixson and E. Dorward-King, “Accumulation of Heavy Metals by Vegetables Grown in Mine Wastes,” Environmental Toxicology and Chemistry, Vol. 19, No. 3, 2000, pp. 600-607. doi:10.1002/etc.5620190311
[14]	D. M. Zhou, X. Z. Hao, Y. J. Wang, Y. H. Dong and L. Cang, “Copper and Zn Uptake by Radish and Pakchoi as Affected by Application of Livestock and Poultry Manures,” Chemosphere, Vol. 59, No. 2, 2005, pp. 167-175. doi:10.1016/j.chemosphere.2004.11.008
[15]	WHO, “Environmental Health Criteria 17. Manganese,” World Health Organization, Geneva, 1981.
[16]	R. Lucchini, E. Albini, L. Benedetti, S. Borghesi, R. Coccaglio, E. Malara, G. Parrinello, S. Garattini, S. Resola and L. Alessio, “High Prevalence of Parkinsonian Disorders Associated to Manganese Exposure in the Vicinities of Ferroalloy Industries,” American Journal of Industrial Medicine, Vol. 50, No. 11, 2007, p. 788. doi:10.1002/ajim.20494
[17]	L. Borgese, A. Zacco, S. Pal, E. Bontempi, R. G. Lucchini, N. J. Zimmerman and L. E. Depero, “A New Non-Destructive Method for Chemical Analysis of Particulate Matter Filters: The Case of Manganese Air Pollution in Vallecamonica (Italy),” Talanta, Vol. 84, No. 1, 2011, pp. 192-198. doi:10.1016/j.talanta.2010.12.048
[18]	R. Lucchini, S. Guazzetti, S. Zoni, F. Donna, S. Peter, A. Zacco, M. Salmistraro, E. Bontempi, N. J. Zimmerman and D. R. Smith, “Tremor, Olfactory and Motor Changes in Italian Adolescents Exposed to Historical Ferro-Manganese Emission,” Neurotoxicology, 2012, in press. doi:10.1016/j.neuro.2012.01.005
[19]	A. Zacco, S. Resola, R. Lucchini, E. Albini, N. Zimmerman, S. Guazzetti and E. Bontempi, “Analysis of Settled Dust with X-Ray Fluorescence for Exposure Assessment of Metals in the Province of Brescia, Italy,” Journal of Environmental Monitoring, Vol. 11, 2009, pp. 1579-1985. doi:10.1039/b906430c
[20]	Ministerial Decree, “Official Methods for Soil Chemical Analysis D.M. n. 185,” Rome, September 13, 1999.
[21]	Ph. Quevauviller, G. Rauret, J.-F. López-Sánchez, R. Rubio, A. Ure and H. Muntau, “Use of a Certified Reference Material for Extractable Trace Metals to Assess Sources of Uncertainty in the BCR Three Stage Sequential Extraction Procedure,” Analytica Chimica Acta, Vol. 382, No. 3, 1999, pp. 317-327. doi:10.1016/S0003-2670(98)00754-5
[22]	G. Rauret, J. F. Lopez-Sanchez, A. Sahuquillo, E. Barahona, M. Lachica, AM. Ure, C. M. Davidson, A. Gomez, J. Bacon, M. Yli-Halla, H. Mautau and P. Quevauviller, “Application of a Modified BCR Sequential Extraction (ThreeStep) Procedure for the Determination of Extractable Trace Metal Contents in a Sewage Sludge Amended Soil Reference Material (CRM 483), Complemented by a Three Year Stability Study of Acetic Acid and EDTA Extractable Metal Content,” Journal of Environmental Monitoring, Vol. 2, No. 3, pp. 22
[23]	K. F. Mossop and C. M. Davidson, “Comparison of Original and Modified BCR Sequential Extraction Procedures for the Fractionation of Copper, Iron, Lead, Manganese, and Zinc in Soils and Sediments,” Analytica Chimica Acta, Vol. 478, No. 1, 2003, pp. 111-118. doi:10.1016/S0003-2670(02)01485-X
[24]	E. Bontempi, A. Zacco, D. Benedetti, L. Borgese, P. Colombi, H. Stosnach, G. Finzi, P. Apostoli, P. Buttini and L. E. Depero, “Total Reflection X-Ray Fluorescence (TXRF) for Direct Analysis of Aerosol Particle Samples,” Environmental Technology, Vol. 31, No. 5, 2010, pp. 467-477. doi:10.1080/09593330903513260
[25]	F. J. Antosz, Y. Q. Xiang, A. R. Diaz and A. J. Jensen, “The Use of Total Reflectance X-Ray Fluorescence (TXRF) for the Determination of Metals in the Pharmaceutical Industry,” Journal of Pharmaceutical and Biomedical Analysis, Vol. 62, 2012, pp. 17-22. doi:10.1016/j.jpba.2011.12.020
[26]	L. Borgese, A. Zacco, E. Bontempi, P. Colombi, R. Bertuzzi, E. Ferretti, S. Tenini and L. E. Depero, “Total Reflection of X-Ray Fluorescence (TXRF): A Mature Technique for Environmental Chemical Nanoscale Metrology,” Measurement Science and Technology, Vol. 20, No. 8, 2009, Article ID 084027. doi:10.1088/0957-0233/20/8/084027
[27]	“R Development Core Team, R Foundation for Statistical Computing,” Vienna, 2009.
[28]	US Department of Energy, Office of Environmental Management, “Empirical Models for the Uptake of Inorganic Chemicals from Soil by Plants,” 1998.
[29]	K. Chojnacka, A. Chojnacki, H. Gorecka and H. Gorecki, “Bioavailability of Heavy Metals from Polluted Soils to Plants,” Science of the Total Environment, Vol. 337, No. 1-3, 2005, pp. 175-182. doi:10.1016/j.scitotenv.2004.06.009
[30]	Y. J. Cui, Y.-G. Zhu, R. H. Zhai, Y. Z. Huang, Y. Qiu and J. Z. Liang, “Transfer of Metals from Soil to Vegetables in an Area near a Smelter in Nanning, China,” Environment International, Vol. 30, No. 6, 2004, pp. 785-791. doi:10.1016/j.envint.2004.01.003
[31]	H. T. Shacklette, J. C. Hamilton, J. G. Boerngen and J. M. Bowles, “Elemental Composition of Surficial Materials in the Coterminous United States,” US Geological Survey, Washington DC, 1971, Professional Paper 574-D.
[32]	W. C. Cooper, “The Health Implications of Increased Manganese in the Environment Resulting from the Combustion of Fuel Additives: A Review of the Literature,” Journal of Toxicology and Environmental Health, Vol. 14, No. 1, 1984, pp. 23-46. doi:10.1080/15287398409530561
[33]	D. C. Adriano, “Trace Elements in the Terrestrial Environment,” Springer-Verlag, New York, 1986.
[34]	W. H. Schroeder, M. Dobson and D. M. Kane, “Toxic Trace Elements Associated with Airborne Particulate Matter: A Review,” Journal of the Air Pollution Control Association, Vol. 37, 1987, pp. 1267-1285.
[35]	W. P. Eckel and W. D. Langely, “A Background-Based Ranking Technique for Assessment of Elemental Enrichment in Soils at Hazardous Waste Sites,” Proceedings of the 9th National Conference, Silver Spring, Hazardous Materials Control Research Institute, Washington DC, 1988, pp. 282-286.
[36]	S. K. Rope, W. J. Arthur, T. H. Craig and E. H. Craig, “Nutrient and Trace Elements in Soil and Desert Vegetation of Southern Idaho,” Environmental Monitoring and Assessment, Vol. 10, No. 1, 1988, pp. 1-24. doi:10.1007/BF00394252
[37]	M. N. V. Prasad and J. Hagemeyer, “Heavy Metal Stress in Plants, from Molecules to Ecosystems,” Springer-Verlag, Berlin, 1999, pp. 51-71.
[38]	F. Itanna, “Metals in Leafy Vegetables Grown in Addis Ababa and Toxicological Implications,” The Ethiop Journal of Health Development, Vol. 16, 2002, pp. 295-302.
[39]	B. S. Ismail, K. Farihah and J. Khairiah, “Bioaccumulation of Heavy Metals in Vegetables from Selected Agricultural Areas,” Bulletin of Environmental Contamination and Toxicology, Vol. 74, No. 2, 2005, pp. 320-327. doi:10.1007/s00128-004-0587-6
[40]	AOAC, “Official Method of Analysis Association of Official Chemists,” 14th Edition, Sidney Williams., Inc. Virginia, 1984.
[41]	K. Callow, “Know Your Micros before You Apply,” 2010. http://www.omafra.gov.on.ca/english/crops/hort/news/hortmatt/2003/14hrt03a3.htm
[42]	M. I. Sheppard and D. H. Thibault, “Natural Uranium Concentrations of Native Plants over a Low-Grade Ore Body,” Soil Science Society of American Journal, Vol. 56, No. 2, 1992, pp. 415-423. doi:10.2136/sssaj1992.03615995005600020012x
[43]	D. Cowan, “Manganese, Measure and Manage,” Agri-Food Laboratories CCA, 2005.
[44]	D. Cowan, “Plant Sampling and Testing Information, Measure and Manage,” Agri-Food Laboratories CCA, 2005.