Abstract—Mass production of plastics began just six decades ago and has rapidly accelerated, creating 8.3 billion metric tons of waste, which exists mostly as disposable products that end up as trash. Incorporating plastic waste in the design of roads can be one alternative for preventing further pollution and minimizing existing plastic waste. The purpose of this research is to characterize the potential risks associated with the implementation of plastic to asphalt. Samples included the following Low-Density Polyethylene (LDPE) plastic bags, and plastic pellets. These samples were tested for the concentration of Lead (Pb), Cadmium (Cd), and Chromium (Cr). All samples were digested and analyzed using: Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) testing, Atomic Absorption Spectrometer (AA) testing, X-Ray Fluorescence Spectrometer (XRF) testing, and the Fourier Transform Infrared Spectrophotometer (FTIR). XRF results indicated that black plastic bags had 0.132% of Cr and white plastic bags had 0.01% of Cr. All the other metals in consideration were non-detect or in the parts per trillion range. The extraction results using the ICP-AES indicated Pb concentrations of 12 mg/kg which does not exceed the USEPA permissible standards. Additional testing for Manganese (Mn), Nickel (Ni), and Antimony (Sb) will be conducted in upcoming procedures. Index Terms—Heavy metals in plastic, LDPE, plastics, sustainability. I. INTRODUCTION Plastics are defined as polymeric compounds with a high molecular mass and are classified by the chemical structure of a polymer's backbone and side chains. Some advantages of plastics are that they have high thermal and electrical insulation properties while remaining low-cost, lightweight, strong, and durable corrosion-resistant materials [1]. Typically, light weight plastics are simple polymers consisting of random-length (but generally very long) chains made up of two-carbon units, as shown in Fig. 1. Fig. 1. Chemical composition of light weight plastic. From 1950 until about 2012, plastics have seen a growth in production of about 8.7 percent per year, increasing from 1.7 million tons to the nearly 300 million tons present today [2]. Among the various areas of industry that demand plastics- including transportation, construction, health care, food Manuscript received May 9th, 2019; revised June 4, 2019. The authors are with Wentworth Institute of Technology, City of Boston, Massachusetts, United States (e-mail: gabby3k7@gmail.com, fmendescatarina@gmail.com). products, telecommunications, and consumer goods- the packaging industry is responsible for the majority of plastic demand, representing 42 percent of the demand in the United States and 40 percent in Europe [3]. From the large volume of plastics being consumed, a large quantity of end-of-life plastics are disposed of to landfills [4]. However, the disposal of plastic products in landfills has become a concern due to the continuous decrease of available space in landfills as well as the potential for plastic leaching when plastic material is deposited in an unlined landfill [5]. During the manufacturing process of plastic bags and packaging, different types of polymers are often used. These include heavy metals and additives [6]. In addition, the compounds within plastic break down very slowly due to their high molecular mass and the formation of polymers, resulting in a very slow decomposition [7], [8]. Once in landfills, these additives can potentially leach into the environment throughout their life-cycle when exposed to light, heat, or other stimulants [9], consequently representing a threat to the health of the population and environment. The urgent need to reduce plastic presence in the environment has resulted in some countries, such as the Netherlands and India, to incorporate plastic into their roadways as a substitute of bitumen. Both plastic and bitumen- which is the major component of asphalt- originate from petroleum. Thus incorporating plastic in asphalt would serve as a possible alternative to recycling plastic. However, most countries are hesitant to incorporate plastic products into roadways as they believe that plastic breaks down into microplastics, which have the ability to adsorb various other contaminants [10]. The construction of roads required large amounts of various materials. Therefore, incorporating even small quantities of reclaimed material into the design of roadways could lead to the repurpose of significant quantities of polyethylene waste [11]. The incorporation of plastics into the design of roads has been proven by studies to add several advantageous qualities to asphalt. Some of these include increased strength, improved binding, and better surface conditions for a prolonged period of exposure to varying climate conditions, thus making tar roads suitable even during heavy traffic [12]. Thus, this alternative can prove to be an easy method to achieve sustainability within infrastructure. Among the various types of plastic, this research primarily focuses on the recycling of Low-Density Polyethylene (LDPE) such as Plastic Bags (PB) and Plastic Pellets (PP). Due to demand within the retail industry and among consumers themselves, PBs have gained increasing popularity [13], [14]. Annually, about 500 billion to one trillion PBs are consumed worldwide; i.e., 1.4–2.7 billion per day, the equivalent of roughly one million bags used per minute [15]. In a study produced by Redford in “Sources of Using Plastic Bags in Roadways Gabriela Kuran, Catarina Figueiredo Mendes, and Gautham Das International Journal of Environmental Science and Development, Vol. 10, No. 12, December 2019 456 doi: 10.18178/ijesd.2019.10.12.1216