Association between microplastic concentration in whole blood and risk of colorectal cancer in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial

Principal Investigator

Name
Rena Jones

Degrees
PhD, MS

Institution
National Cancer Institute

Position Title
Senior Investigator

Email
rena.jones@nih.gov

About this CDAS Project

Study
PLCO (Learn more about this study)

Project ID
2025-0059

Initial CDAS Request Approval
Jan 26, 2026

Title
Association between microplastic concentration in whole blood and risk of colorectal cancer in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial

Summary
Plastic production has increased over the past decades, and exposure to fine plastic particles in the environment has become an increasing concern for human health. Microplastics (MPs) are small plastic particles with regular or irregular shape and with diameter ranging from 0.1 µm (nanoplastics) to 5 mm, and are byproducts formed during intentional plastic manufacture for use in personal-care and cleaning products, manufacturing of materials containing plastics, and degradation of plastics. As consumption of contaminated food and beverages is a major source of MPs, the gastrointestinal tract is thought to be a main route of human exposure to MPs. Experimental and animal studies have previously linked exposure to MPs to potential risk of colorectal cancer (CRC) as studies found exposure to MPs can lead to infmalation and disfunction of the intestinal barier, as well as result in intestinal toxicity by damaging the integrity of the colonic mucas and thereby reducing the gut protective function. To date, no molecular epidemiological study has investigated the link between MP exposure and risk of colorectal cancer (CRC). We propose to evaluate this association in a nested case-control study in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial.

To address this gap in knowledge, we propose to collaborate with Dr. Douglas Walker at Emory University to measure MP concentration in human whole blood using his laboratory and quantitative method: Fast, Single Tissue Extraction for Multiplexed Plastics Analysis (FaSTE-MPA). The FaSTE-MPA method has been previously validated and has shown to reliably measure MP concentration in human tissues. To assess the association between MP and CRC risk, we will measure MP concentrations in whole blood samples (1.8 ml) from PLCO’s 312 CRC cases and 312 matched controls with available serum metabolites data, as well as 30 duplicate samples from controls to be used for quality control. Specifically, we will:

Aims

Primary Aim 1. Measure MP concentrations in 312 CRC cases and 312 matched controls using FaSTE-MPA and describe the distribution of MP concentration overall and by all matching factors, including age, sex, smoking status, study center, body mass index, and time of sample collection.

Primary Aim 2. Evaluate the relationship between MP concentration and future risk of CRC.

Secondary Aim 1. Assess the association between MP concentration and previously measured 676 serum metabolites.

We hypothesize we will observe a difference in distribution of microplastics concentration by the factors listed in aim 1, especially by smoking status, body mass index, study center, and dietary factors. We also hypothesize that we will observe an association between increased microplastics concentration and risk of colorectal cancer, as well as with certain metabolites.

Findings from our study, to our knowledge the first of its kind, may help elucidate the link between exposure of MP and human health as it pertains to colorectal tumorigenesis and contributing to critical knowledge to an emerging area of environmental health.

Collaborators

Rena R. Jones (National Cancer Institute)
Batel Blechter (National Cancer Institute)
Erikka Loftfield (National Cancer Institute)
Qing Lan (National Cancer Institute)
Nathaniel Rothman (National Cancer Institute)
Mohammad L. Rahman (National Cancer Institute)
Mark Purdue (National Cancer Institute)
Douglas Walker (Emory University)