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Atmospheric methane, nonmethane hydrocarbons, and carbon monoxide were measured at the Mauna Loa Observatory on the island of Hawaii in May and June 1988. The daily island upslope/downslope circulation resulted in a variable mixture of boundary layer and free tropospheric air at the observatory. Mixing ratios of these gases were higher during upslope flow than during downslope flow. Mixing ratios characteristic of the free troposphere at this altitude were most often measured during nighttime, downslope flow. Local marine emissions of ethylene and propylene and emissions of isoprene from island vegetation were detected during upslope circulation, but ethylene and propylene were also often detected at night during downslope circulation, indicating that air sampled during nighttime downslope flow may have included some air recently transported from the marine boundary layer. Comparison of data for methane, carbon monoxide, ethane, and propane from in situ measurements with measurements made from canister samples collected during the experiment showed very good agreement. Fluxes of isoprene from selected dominant island flora were also measured.

Within the last 20 years there has been a definite increase in the incidence of thyroid carcinoma. 8,12,15 Both an absolute increase in numbers of cases and a relative increase in comparison with other forms of thyroid disease have been observed. Better diagnostic techniques and their wider usage have undoubtedly contributed to this increase. Some authors believe that we are now discovering the long-term consequences of using radiation to the neck of young children. 3,6,14,15 It is also possible that more children with abnormalities of the branchial cleft derivatives are now surviving to adolescence, where the growth disturbances become apparent as neoplasms. Simultaneously, the relative importance of cancer as a cause of death in children has increased. The discovery and wide use of powerful antimicrobial agents has reduced deaths from respiratory diseases to their present third position. Cancer has now become the second commonest cause of death in childhood, exceeded

Reports from various centers indicate that Hashimoto thyroiditis is increasing in frequency. 9,15,17 There are two schools of thought regarding its treatment, and willingness to use medical treatment depends on confidence in the accuracy of the diagnosis. We have undertaken a study of 1,000 consecutive operations done for nontoxic goiter in an attempt to determine (1) the degree of diagnostic accuracy in current surgical practice; (2) the indications or contraindications for surgical treatment of thyroiditis, and (3) how increasing knowledge of the natural history of Hashimoto thyroiditis may alter some current methods of management. The series of operations was obtained from the files of the U.C.L.A. Medical Center and from two accredited private hospitals near the Medical Center, St. John's and Santa Monica hospitals. All cases of toxic diffuse goiter have been excluded from this study because the ubiquitous lymphoid accumulations accompanying Graves' disease are interpreted by some pathologists as