Assessment of metal contaminations leaching out from recycling plastic bottles upon treatments

• Published in: Environmental science and pollution research international 2010-08, Vol.17 (7), p.1323-1330
• Main Authors: Cheng, Xiaoliang, Shi, Honglan, Adams, Craig D, Ma, Yinfa
• Format: Article
• Language: English
• Subjects: Antimony; Antimony - analysis; Aquatic Pollution; Arsenic - analysis; Atmospheric Protection/Air Quality Control/Air Pollution; Beverages; Bottled water; Coffee; Cold Temperature - adverse effects; Conservation of Natural Resources - methods; Contaminants; Cooling; Drinking water; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental protection; Food contamination & poisoning; Food Contamination - prevention & control; Food Packaging; Heating; Heavy metal content; Heavy metals; High density polyethylenes; Hot Temperature - adverse effects; Hydrogen-Ion Concentration; Irradiation; Leaching; Manufacturers; Manufacturing; Manufacturing industry; Metal concentrations; Metals - analysis; Microwaves; Microwaves - adverse effects; Milk; pets; Plastics; Plastics - chemistry; Plastics - radiation effects; Plastics recycling; Polyethylene terephthalate; Polyethylene Terephthalates - chemistry; Polyethylene Terephthalates - radiation effects; Polymers - chemistry; Polymers - radiation effects; Polyvinyl chloride; Recycling; Recycling plastics; Refuse Disposal - methods; Research Article; Selenium - analysis; Studies; Sunlight; Sunlight - adverse effects; Waste Water Technology; Water - chemistry; Water Management; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-010-0312-4

Background, aims, and scope Heavy metal contaminants in environment, especially in drinking water, are always of great concern due to their health impact. Due to the use of heavy metals as catalysts during plastic syntheses, particularly antimony, human exposure to metal release from plastic bottles has been a serious concern in recent years. The aim and scope of this study were to assess metal contaminations leaching out from a series of recycling plastic bottles upon treatments. Methodology In this study, leaching concentrations of 16 metal elements were determined in 21 different types of plastic bottles from five commercial brands, which were made of recycling materials ranging from no. 1 to no. 7. Several sets of experiments were conducted to study the factors that could potentially affect the metal elements leaching from plastic bottles, which include cooling with frozen water, heating with boiling water, microwave, incubating with low-pH water, outdoor sunlight irradiation, and in-car storage. Results Heating and microwave can lead to a noticeable increase of antimony leaching relative to the controls in bottle samples A to G, and some even reached to a higher level than the maximum contamination level (MCL) of the US Environmental Protection Agency (USEPA) regulations. Incubation with low-pH water, outdoor sunlight irradiation, and in-car storage had no significant effect on antimony leaching relative to controls in bottle samples A to G, and the levels of antimony leaching detected were below 6 ppb which is the MCL of USEPA regulations. Cooling had almost no effect on antimony leaching based on our results. For the other interested 15 metal elements (Al, V, Cr, Mn, Co, Ni, Cu, As, Se, Mo, Ag, Cd, Ba, Tl, Pb), no significant leaching was detected or the level was far below the MCL of USEPA regulations in all bottle samples in this study. In addition, washing procedure did contribute to the antimony leaching concentration for polyethylene terephthalate (PET) bottles. The difference of antimony leaching concentration between washing procedure involved and no washing procedure involved (AC) was larger than zero for samples A to G. This interesting result showed that higher antimony concentration was detected in experiments with no washing procedures compared with those experiments with washing procedures. Our study results indicate that partial antimony leaching from PET bottles comes from contaminations on the surface of plastic during manufacturing