Begley T H, McNeal T P, Biles J E, Paquette K E
Food and Drug Administration, Washington, DC 20204, USA.
Food Addit Contam. 2002;19 Suppl:135-43. doi: 10.1080/02652030110083720.
To evaluate the feasibility of recycling all PET bottles into food packaging, realistic estimates of the maximum concentration of contaminants that might be expected in the polymer are needed. To estimate the maximum concentration of a contaminant that might be in PET from the storage of non-food substances, sorption experiments into two types of PET were performed. These test materials were 0.8mm thick amorphous PET (a relative sink for contaminants) and commercial PET bottle wall. Using a commercial shampoo containing 1% lindane (C6H6Cl6), the test materials were stored in contact with the shampoo at 20 and 40 degrees C for 231 days. This commercial shampoo also represents an extreme case because it contains 7% acetone, a solvent which swells PET, further enhancing sorption of chemicals. Additional sorption experiments into PET were performed by preparing solutions of 10% toluene in Miglyol (a fractionated coconut oil), 10% benzophenone in Miglyol, 5% 2-butoxyethoxy ethanol (2-BE) in 50/50 water/ethanol, and 10% methyl stearate in heptane. Sorption data from the shampoo into PET illustrate Fickian behaviour. Specifically, the amount of sorption at room temperature is approximately40 times less than that at 40 degrees C. The amount of lindane sorbed into PET from the shampoo after 231 days was 0.1 and 3.7 mgdm(-2) at 20 and 40 degrees C respectively. These values correspond to 28 and 765 mg kg(-1) on a mass/mass basis. All sorptions are within the ranges measured and published by other authors using surrogate contamination testing schemes. Additionally, actual bottles from recycle bins were analysed for the amout of contamination. Results are discussed in terms of potential consumer exposure to non-food contaminants in food containers made of recycled PET and in relation to the surrogate testing methods recommended by the Food and Drug Administration (FDA) for determining the compatibility of a PET recycling process to produce containers suitable for food-contact use.
为评估将所有聚对苯二甲酸乙二酯（PET）瓶回收用于食品包装的可行性，需要对聚合物中可能出现的污染物最大浓度进行实际估算。为估算因储存非食品物质而可能存在于PET中的污染物最大浓度，对两种类型的PET进行了吸附实验。这些测试材料为0.8毫米厚的非晶态PET（污染物的相对吸收体）和商用PET瓶壁。使用含有1%林丹（C6H6Cl6）的商用洗发水，将测试材料与洗发水在20℃和40℃下接触储存231天。这种商用洗发水也是一个极端情况，因为它含有7%的丙酮，丙酮是一种会使PET膨胀的溶剂，会进一步增强化学物质的吸附。通过在Miglyol（一种分馏椰子油）中制备10%甲苯溶液、在Miglyol中制备10%二苯甲酮溶液、在50/50水/乙醇中制备5% 2 - 丁氧基乙氧基乙醇（2 - BE）溶液以及在庚烷中制备10%硬脂酸甲酯溶液，对PET进行了额外的吸附实验。从洗发水到PET的吸附数据表明符合菲克行为。具体而言，室温下的吸附量约为40℃时的1/40。231天后，从洗发水中吸附到PET中的林丹量在20℃和40℃时分别为0.1和3.7毫克/平方分米。以质量/质量计，这些值分别对应28和765毫克/千克。所有吸附量都在其他作者使用替代污染测试方案所测量和公布的范围内。此外，还对回收箱中的实际瓶子进行了污染物含量分析。根据消费者在使用由回收PET制成的食品容器时可能接触到非食品污染物的情况，以及食品药品监督管理局（FDA）推荐的用于确定PET回收工艺生产适用于食品接触用途容器兼容性的替代测试方法，对结果进行了讨论。
