Toxic footprint and materials profile of electronic components in printed circuit boards

Jinfeng Huang; Yi Deng; Yunhui Han; Jiancheng Shu; Rong Wang; Sheng Huang; Oladele A Ogunseitan; Keli Yu; Min Shang; Yi Liu; Shuyuan Li; Yubin Han; Zhiqiang Cheng; Mengjun Chen

doi:10.1016/j.wasman.2022.01.019

Toxic footprint and materials profile of electronic components in printed circuit boards

Waste Manag. 2022 Mar 15:141:154-162. doi: 10.1016/j.wasman.2022.01.019. Epub 2022 Feb 2.

Authors

Jinfeng Huang¹, Yi Deng², Yunhui Han¹, Jiancheng Shu¹, Rong Wang³, Sheng Huang⁴, Oladele A Ogunseitan⁵, Keli Yu⁶, Min Shang⁷, Yi Liu⁷, Shuyuan Li², Yubin Han⁸, Zhiqiang Cheng⁸, Mengjun Chen⁹

Affiliations

¹ Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, PR China.
² Solid Waste and Chemical Management Technology Center of the Ministry of Ecological Environment, Beijing 100000, PR China.
³ School of National Defense Science and Technology, Southwest University of Science and Technology, Mianyang 621010, PR China.
⁴ Southwest University Science and Technology, Dept Environmental Engineering, School of Environmental & Resource, Mianyang 621010, PR China.
⁵ Department of Population Health and Disease Prevention, University of California, Irvine, CA 92697-3957, USA.
⁶ China National Resources Recycling Association, Beijing 100037, PR China.
⁷ Sichuan Solid Waste and Chemicals Management Center, Chengdu 610000, PR China.
⁸ Chengdu Loyalty Technology Co., Ltd., Chengdu Aviation Power Industrial Park, Chengdu 611936, PR China.
⁹ Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, PR China. Electronic address: kyling@swust.edu.cn.

PMID: 35123249
DOI: 10.1016/j.wasman.2022.01.019

Abstract

Waste printed circuit boards (WPCBs) contain valuable material resources and hazardous substances, thereby posing a challenge for sustainable resource recovery and environmental protection initiatives. Overcoming this challenge will require mapping the toxic footprint of WPCBs to specific materials and substances used in manufacturing electronic components (ECs). Therefore, this work collected 50 EC specimens from WPCBs in five ubiquitous consumer products, such as television, refrigerator, air conditioner, washing machine and computer. The work extracted and analyzed metal contents and used leachability assessments based on tests adopted by the regulatory policies from China and the United States. The work found that copper and iron are the most abundant constituents in ECs, with concentrations ranging 5.90-796.62 g/kg and 0-831.53 g/kg, respectively; whereas abundance of precious metal content is in the order of silver > gold > palladium > platinum, with silver concentration ranging 15-5290 mg/kg. The content of marginally-regulated toxic substance arsenic ranged 0-9700 mg/kg; whereas fully regulated toxic metals such as chromium, lead and mercury did not exceed the thresholds set by China and US standards. The work found new toxic threats from arsenic and selenium leached from 20 of 50 ECs exceeding regulatory standards. These results will aid manufacturers and recyclers in protecting workers' health and environmental quality from arsenic and selenium pollution, and should initiate discussion about regulating these toxic components as part of a comprehensive program to reduce the toxic footprint of electronic products.

Keywords: E-waste; Electronic components; Leaching Assessment; Printed Circuit Boards; Regulatory Policy; Toxic Footprint.