Aims: (a) To compare in the laboratory the effectiveness of various filters at removing particles from
heroin injections; (b) To measure the amount of heroin retained by the filters; and (c) To describe the
relevance of these preliminary findings to future research.
Design: A laboratory-based investigation. Injections were prepared with street heroin obtained from
the police, copying the methods of injectors. Pieces of cigarette filter, hand-rolling cigarette filter,
cotton wool from buds and commercially produced syringe filters were tested. The Coulter Multisizer
(IIe) was used to count and size particles; Capillary Zone Electrophoresis was used to measure the
amount of heroin retained in the filters.
Findings: All methods of filtration reduced the amount of particles, with the commercially produced
syringe filter producing the largest reduction. The syringe filter retained the most heroin after use;
however, less drug material was evident on the spoon, suggesting further work is needed with a range
of quantities. The cigarette, hand-rolling and cotton bud filters all retained some drug with no
significant difference detected between the different filters.
Conclusions: This preliminary study suggests all the filters tested may convey health benefits. Further
work is needed with varying quantities of drug, acid and water and to establish safety in use. Then
future studies can establish the health consequences for injecting drug users from the use of such