Spatiotemporal trends in discarded needle reports near schools in Boston, Massachusetts, between 2016-2019

Childhood exposures to discarded needles pose a direct risk for infection with blood-borne pathogens and psychological trauma for caregivers and children. Little is known about environmental predictors of discarded needles relative to areas where children are frequent, such as schools.

We investigated spatiotemporal trends in discarded needle reports and the density near schools in Boston, Massachusetts, between 2016 and 2019.

We used the kernel density estimation (KDE) and a relative risk function (RRF) to explore their spatial distribution and temporal changes of discarded needles reported through the 311 service request system in Boston. The density of needle pick-up requests around schools was investigated by using Thiessen polygons.

Between January 2016 and December 2019, 18,272 discarded needle reports were made. Publicly reported discarded needles in Boston sharply increased over the 4 years and the highest density of needles was found in 2 central neighborhoods. The density of reports of discarded needles near schools increased among the majority of schools. About 30% of schools demonstrated an increase of 100% or more in reports of discarded needles.

This analysis provides insight into potential risk of exposure to needle stick injuries for children based on utilizing publicly available crowd-sourced data. Monitoring the density of discarded needles near schools may be a novel approach to improve public health efforts to distribute safe needle disposal locations and reduce injection drug use in public.