31. Because a day care center is next door, they are conducting air sampling and soil tests. 32. Like most scientists who study air samples , Portnoy had assumed these were just bits of soot. 33. The crew was to take air samples in higher altitudes to check the pollution-threatened ozone layer. 34. On 41 different days, researchers took air samples in the market, and consistently found fish allergens. 35. Environmental Protection Agency investigators took air samples Thursday to determine if there was any residual contamination. 36. Williams frequently encountered the black specks on his microscope slides while studying air samples in Denver. 37. American air samples returned to Earth on Oct . 27 reached the United States earlier this week. 38. Portable field sensors can screen air samplings and give an initial analysis within 15 minutes, he said. 39. Meantime, EPA assistant administrator Timothy Fields said the EPA began taking air samples near the incinerator Wednesday. 40. Narlikar was part of a study which cultured microorganisms from stratospheric air samples obtained at 41 km.