In the present study, the varieties of papers and paperboards (PPBs) used in India for food packaging were qualitatively and quantitatively analyzed for the heavy metal contamination with the help of ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry). Total 10 different types of food packaging PPBs were procured from local market and analyzed for 14 heavy metals (Al, As, B, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Te, Ti and V). Quantities of heavy metals in the samples were compared with permitted values published by the European Council. Heavy metals like Al, As, Ba, Cr, Co, Ni, Pb and V were observed in more than the permitted concentration in some of the samples. Heavy metals toxicity in food packaging material is a serious concern as the edible items get exposed to these metals and also generate volatile odorous compounds which considerably impact the quality of food and affect consumer's health.
Food packaging PPBs are the most widely used source of food packaging all over the world [
Heavy metals are a big source of environment pollution [
Although studies have focused on assessing the heavy metal levels in food packaging, but there is no information available on the content of heavy metals in Indian food packaging PPBs. The interest of present work lies in qualitative and quantitative monitoring of heavy metal levels in locally procured food packaging PPBs.
In this study the samples of total 10 food packaging PPBs have been collected from local markets. The study of analysis of heavy metals was conducted to keeping the heath concern in mind. 10 food PPBs which are used for direct food packaging were purchased from different confectionary stores situated in different parts of the city. In additional testing, 3 samples of each group of food packaging PPBs were purchased from the local retail outlets. The samples included paper plate, cake box, fruit tray, tissue paper, coffee cup, pastry box, sweet box, pizza box, French fries box, and paper bag. These food packaging paper are founds in frequently in the markets.
Closed vessel microwave system (Marsxpress; CEM, USA) was used for the digestion of samples. Operating conditions were followed as per the USEPA 3051 method. Digested solutions were cooled, filtered and diluted to 10 ml with distilled water, prior to ICP-OES analysis. Multi-element standard (REICPCAL29A) was used to standardize and calibrate the metal concentration. Analytical reagents-grade chemicals and double distilled water were used for the preparation of solutions and dilutions respectively.
In the present study, 10 commercially available food packaging PPBs were checked for the presence of 14 heavy metals, which are generally present as residues of the recycling process and due to their presence in paper and pulp industry, so as to determine their suitability to be used as packaging materials which come in direct contact with foodstuffs.
Heavy metal content in 10 different types of locally procured food packaging PPBs is shown in
Heavy metals Sample | Al | As | B | Ba | Co | Cr | Cu | Fe | Mn | Ni | Pb | Te | Ti | V |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Permitted conc. (ppm) | 5 | 0.002 | - | 1.2 | 0.02 | 0.250 | 4 | 40 | 1.8 | 0.14 | 0.010 | - | - | 0.01 |
Paper Plate | 59.204 ± 0.160 | 0.109 ± 0.012 | 0.008 ± 0.001 | 0.687 ± 0.001 | 0.024 ± 0.001 | 0.602 ± 0.008 | 0.545 ± 0.001 | 15.919 ± 0.036 | 0.547 ± 0.001 | 0.089 ± 0.005 | 0.388 ± 0.007 | 0.012 ± 0.005 | 0.007 ± 0.068 | 0.373 ± 0.001 |
Cake Box | 32.063 ± 0.035 | 0.008 ± 0.012 | 0.012 ± 0.000 | 0.379 ± 0.000 | Nd | 0.159 ± 0.007 | 0.677 ± 0.001 | 11.847 ± 0.012 | 0.272 ± 0.000 | 0.027 ± 0.004 | 0.111 ± 0.003 | 0.011 ± 0.008 | Nd | 0.269 ± 0.000 |
Fruit Tray | 22.738 ± 0.049 | Nd | Nd | 0.284 ± 0.000 | Nd | 0.237 ± 0.004 | 0.790 ± 0.000 | 5.910 ± 0.003 | 0.322 ± 0.000 | 0.008 ± 0.001 | 0.112 ± 0.005 | 0.012 ± 0.005 | Nd | 0.127 ± 0.000 |
Tissue Paper | 11.763 ± 0.018 | Nd | Nd | 0.568 ± 0.000 | Nd | 0.118 ± 0.001 | 0.045 ± 0.000 | 0.418 ± 0.002 | Nd | Nd | Nd | 0.009 ± 0.007 | Nd | 0.032 ± 0.000 |
Coffee Cup | 86.092 ± 0.458 | 0.191 ± 0.008 | 0.008 ± 0.003 | 0.271 ± 0.001 | 0.053 ± 0.000 | 1.829 ± 0.173 | 0.214 ± 0.001 | 4.667 ± 0.024 | 0.333 ± 0.001 | 0.078 ± 0.010 | 0.061 ± 0.004 | Nd | Nd | 0.404 ± 0.002 |
Pastry Box | 13.175 ± 0.107 | Nd | Nd | 1.118 ± 0.005 | Nd | 2.174 ± 0.091 | 0.511 ± 0.002 | 5.046 ± 0.018 | 0.311 ± 0.001 | 0.033 ± 0.004 | Nd | 0.007 ± 0.007 | Nd | 0.227 ± 0.000 |
Sweet Box | 46.644 ± 0.087 | 0.081 ± 0.017 | Nd | 0.265 ± 0.000 | Nd | 0.255 ± 0.012 | 0.452 ± 0.002 | 8.704 ± 0.032 | 0.208 ± 0.000 | 0.100 ± 0.000 | 0.232 ± 0.001 | Nd | Nd | 0.220 ± 0.001 |
Pizza Box | 102.722 ± 0.264 | 0.300 ± 0.024 | 0.015 ± 0.000 | 0.832 ± 0.002 | Nd | 0.452 ± 0.005 | 0.832 ± 0.002 | 37.209 ± 0.101 | 0.439 ± 0.001 | 0.196 ± 0.004 | 0.339 ± 0.002 | 0.005 ± 0.008 | Nd | 0.547 ± 0.001 |
French Fries Box | 33.950 ± 0.114 | 0.028 ± 0.010 | 0.035 ± 0.000 | 0.289 ± 0.001 | Nd | 0.092 ± 0.003 | 0.543 ± 0.002 | 7.657 ± 0.029 | 0.285 ± 0.001 | 0.079 ± 0.002 | 0.083 ± 0.003 | 0.004 ± 0.002 | Nd | 0.152 ± 0.000 |
Paper Bag | 46.998 ± 0.064 | 0.097 ± 0.018 | Nd | 0.281 ± 0.000 | Nd | 0.026 ± 0.001 | 0.328 ± 0.000 | 4.038 ± 0.010 | 0.237 ± 0.000 | 0.095 ± 0.001 | 0.051 ± 0.004 | Nd | 0.153 ± 0.073 | 0.232 ± 0.000 |
*Nd―Not detected.
Co-0.02, Cr-0.250, Cu-4, Fe-40, Ni-0.14, Pb-0.010, and V-0.01 [
Upto 100 mg/kg of manganese has been found to be present in wood, which could be the reason for its presence in all the samples that were examined [
Over the last two decades, wood preservation scientists have refocused on the use of boron due to its favorable environmental characteristics [
In this study, all samples contained Mn, Cu, and Fe within the permitted concentration. However, the presence of Mn, Cu and Fe ions in the paper and paperboard food packages catalyses the initiation of autoxidation of unsaturated
fatty acids leading to the formation of odorous volatile compounds like aldehydes, ketones, and alcohols which brings an unpleasant feeling in the customer and may lead to rejection of food even though the food has been spoiled or not [
In summary, this is a comprehensive research on the occurrence of a wide range of heavy metals in various samples of Indian food packaging PPBs. Comparison of the measured concentrations with permitted standards suggests that the presence of these contaminants may be associated with health hazards. The findings of this study will aid in understanding of the potential risk of rejection of food packages due to odorous compounds generation which is catalyzed by heavy metals. Future studies and regulatory actions should focus on strict monitoring of packaging materials at all stages, starting from raw material selection, storage, paper production, and till it reaches the consumer.
The authors are grateful to Central Instrumentation Facility, IIT Roorkee (SRE Campus) and Ministry of Human Resource Development (MHRD), India; fellowship contingency for carrying out this work.
The authors declare no conflicts of interest regarding the publication of this paper.
Sood, S. and Sharma, C. (2019) Levels of Selected Heavy Metals in Food Packaging Papers and Paperboards Used in India. Journal of Environmental Protection, 10, 360-368. https://doi.org/10.4236/jep.2019.103021