Comparing the effectiveness of interventions to improve ventilation behavior in primary schools.

UNLABELLED: Poor air quality in schools has been associated with adverse health effects. Indoor air quality can be improved by increasing ventilation. The objective of this study was to compare the effectiveness of different interventions to improve ventilation behavior in primary schools. We used indoor CO(2) concentrations as an indicator. In 81 classes of 20 Dutch primary schools, we applied three different interventions: (i) a class-specific ventilation advice; (ii) the advice combined with a CO(2) warning device and (iii) the advice combined with a teaching package. The effectiveness of the interventions was tested directly after intervention and 6 weeks after intervention by measuring the CO(2) concentrations and comparison with a control group (iv). Before intervention, the CO(2) concentration exceeded 1000 ppm for 64% of the school day. The class-specific ventilation advice without further support appeared an ineffective tool to improve ventilation behavior. The advice in combination with a CO(2) warning device or the teaching package proved effective tools and resulted in lower indoor CO(2) concentrations when compared with the control group. Ventilation was significantly improved, but CO(2) concentrations still exceeded 1000 ppm for more than 40% of the school day. Hence, until ventilation facilities are upgraded, the CO(2) warning device and the teaching package are useful low-cost tools. PRACTICAL IMPLICATIONS: To improve ventilation behavior and indoor air quality in schools, CO(2) warning device and teaching package combined with a class-specific ventilation advice, are effective tools, while giving the ventilation advice solely, is not effective. Although ventilation is significantly improved through behavioral change, the ventilation rate is still insufficient to maintain good air quality during the full school day. Therefore, the improvement of the ventilation facilities is recommended. Hence, until ventilation facilities in schools are upgraded, the CO(2) warning device and the teaching package are useful low-cost tools to improve current indoor air quality.

Time-resolved fluoroimmunoassay for unconjugated estrogen in urine: comparison with a fluorometric assay for total estrogen and application in an in vitro fertilization program.

A time-resolved fluoroimmunoassay (TR-FIA) for unconjugated estrogens in human urine is described. 6-Keto-17 beta-estradiol-6-(O-carboxymethyl)oxime:bovine serum albumin is immobilized onto microtiter strip wells and the coated wells are incubated with 17 beta-estradiol standard preparations or unknowns with a polyclonal antiserum to 17 beta-estradiol-16,17-monosuccinyl:albumin. The antiserum-bound estrogen is detected by incubation with a europium-labeled anti-rabbit IgG that serves as both second antibody and tracer. After the immunoreactions, the bound portion of the labeled antiserum is quantified by dissociating the Eu3+ in a fluorescence-enhancement solution and measuring its fluorescence with a time-resolved fluorometer. The detection limit of the TR-FIA is 24 pmol of 17 beta-estradiol per liter; the analytical range extends to 1.8 nmol/L. This assay is a convenient alternative to radioimmunoassay and to the automated Kober-Ittrich fluorometry of total estrogen. Its advantages include short counting times; use of nonradioactive, stable reagents, all of which are commercially available; and more nearly complete automation. We conclude that this TR-FIA, compared with the Kober-Ittrich fluorometric assay (J Endocrinol 1957; 16:49-56), provides the clinician with equivalent information during follicular development therapy as part of an in vitro fertilization program.