Evaluation of exposure to man-made vitreous fibers by nasal lavage

Fiberglass and Other Flame-Resistant Fibers in Mattress Covers

Public complaints have raised concerns that some mattresses in the current marketplace may be potential sources of airborne fiberglass. Although mattress foam is often marketed as chemical-free, their cover compositions are not as well understood by the general public. To fill these basic information gaps, the covers of four newly purchased mattresses were sampled and analyzed using polarized light microscopy, SEM-EDS, and FTIR microspectroscopy. Two of the mattress covers contained over 50% fiberglass in their inner sock layers. Up to 1% of the fiberglass had migrated to adjacent fabric layers, representing a potential risk of consumer exposure if the zipper on the outer cover is opened. The observed fiberglass fragments had calculated aerodynamic diameters ranging between 30 and 50 µm, suggesting they are potentially inhalable into the nose, mouth, and throat, but are likely too large to penetrate deeper into the lungs. No fiberglass was observed on the brand new mattresses’ outer surfaces. Synthetic fibers also present in the sock layers were consistent with flame resistant modacrylic containing vinyl chloride and antimony. The use of fiberglass and other chemicals in mattress covers poses a potential health risk if these materials are not adequately contained. The apparent non-inclusion of mattress covers in chemical-free certifications suggests that further improvements are needed in mattress labeling and education of consumers.

The normative value of inflammatory cells in the nasal perfusate of Chinese adults: a pilot study

OBJECTIVE

To establish stable, well-accepted nasal perfusion and a normative value of classifying cells in the nasal perfusate of Chinese adults.

METHODS

A total of 500 healthy adults were divided into two groups of 250 people per group (group A, 16-30 years old and group B, 31-60 years old; male-to-female ratio, 1:1). All volunteers were non-smokers; they were irrigated with saline, and multiple inflammatory cells in the perfusate were analyzed.

RESULTS

Irrigation was successfully performed in 479 cases, a success rate of 95.80%. The types of inflammatory cells showed a skewed distribution. The median number and interquartile range (IQR) of eosinophils were 0 and 0.2, respectively. These values were 0.4 and 2.2, respectively, for neutrophils and 0 and 0, respectively, for both lymphocytes and macrophages. There was no significant difference between males and females (P>0.05). There was a significant difference in the numbers of neutrophils and lymphocytes in the different age groups (P=0.000), but there was no significant difference in the numbers of eosinophils and macrophages (P>0.05). The 95% unilateral upper limited values (UULVs) of eosinophils and neutrophils in the nasal perfusates were 2.99 and 14.94, respectively, for group A and 1.41 and 17.08 for group B. As a result, the total 95% UULVs of eosinophils and neutrophils in the nasal perfusate were 2.00 and 16.80.

CONCLUSIONS

We established stable, well-accepted nasal perfusions and normal values for classifying the cells in the nasal perfusate of Chinese adults; the normative values of the inflammatory cells in nasal perfusate are 2.00 for the 95% UULV of eosinophils and 16.80 for neutrophils. Age might be one of the factors affecting the cells in rhinitis.

Man-made vitreous fibers in office buildings in the Helsinki area

Several sources of man-made vitreous fibers (MMVFs) may exist in an office environment causing irritation symptoms among occupants. In 258 office buildings, the occurrence and density of settled MMVFs on surfaces were measured by two sampling methods. Altogether, 1113 samples of settled dust were collected from surfaces with plastic bags and gelatine tape and were analyzed with a scanning electron microscope and a stereomicroscope, respectively. Tape samples from 68 buildings were collected from frequently cleaned (n = 162) and seldom cleaned (n = 57) room surfaces in 56 and 29 offices, respectively, and from supply air ducts (n = 24) in 10 offices. MMVFs longer than 20 microm were counted with a stereomicroscope. Irritation symptoms were recorded with a questionnaire. More than 60% of the surface dust and almost 90% of the samples collected from supply air ducts contained MMVFs. The density of MMVFs longer than 20 microm ranged from < 0.1 to 5 fiber cm(- 2). The mean density of the MMVFs was about two times higher on the seldom cleaned surfaces than on the frequently cleaned surfaces. The density was usually under 0.2 MMVF cm(- 2) in surface dust of offices without emission sources of MMVFs. The measurements combined with qualitative analysis of settled dust can help to localize relevant sources of fiber emissions. Altogether, in 40% of the buildings, several occupants had repeated irritation symptoms that were verified by occupational health care personnel.