SmokeScreen is the first commercial example of a device called SafeTube. This is a patented technology which allows quick and easy-to-use colorimetric and other assays to be carried out away from the laboratory without the need for expensive instrumentation. The device allows reactive chemicals to be isolated from one another before the test and safely contains reagents and sample after use, reducing the chance of operator contamination and allowing for safe disposal.

SmokeScreen, the 6-minute urine test can be used on its own to correctly identify smokers, with a colour chart for a semi-quantitative measure of smoking and urine can be analysed with the new dedicated colorimeter for a quantitative measure of nicotine intake. This instrument is sensitive enough to detect down to passive smoking levels. The colorimetric assay used turns a urine sample different shades of pink.

Measurement of nicotine metabolites is significantly more reliable in determining smoking habit than self reported cigarette consumption and is more specific and longer lasting than carbon monoxide monitoring.

SmokeScreen is a 6-minute colorimetric test which detects nicotine and all its breakdown products, with a positive sample turning a pink/orange colour. The test can be used in three ways: observing a colour change will tell whether the sample is from a smoker or not.

A colour chart for a semi-quantitative assessment of nicotine intake can be used, or a dedicated colorimeter will quantify nicotine metabolite concentration against a cotinine standard.

A colorimeter will mix the sample, time the assay and display the result – Cotinine Equivalent Concentration against a built-in cotinine standard curve (0-20 mg/ml). The type of smoker will also be displayed: non-smoker; passive smoker; light; medium; heavy and v.heavy.