Relative Importance of Different Water Categories as Sources ofN-Nitrosamine Precursors

Relative Importance and Contribution of Anthropogenic and Natural Sources of Nitrosamine Precursors

Occurrence of nine nitrosamines and secondary amines in source water and drinking water: Potential of secondary amines as nitrosamine precursors.

Due to their high carcinogenicity, the control of nitrosamines, a group of disinfection by-products (DBPs), is an important issue for drinking water supplies. In this study, a method using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry was improved for simultaneously analyzing nine nitrosamines in source water and finished water samples of twelve drinki...

Quaternary amines as nitrosamine precursors: a role for consumer products?

Nitrosamine formation has been associated with wastewater-impacted waters, but specific precursors within wastewater effluents have not been identified. Experiments indicated that nitrosamines form in low yields from quaternary amines, and that the nitrosamines form from the quaternary amines themselves, not just lower order amine impurities. Polymeric and benzylated quaternary amines were more...

Relative importance of various income sources of the aged, 1980.

This article looks at the extent to which aged couples and nonmarried persons rely on earnings, retirement pensions, assets, and public assistance. The study notes the importance of these various sources to aged units with different levels of both total money income and retirement income, then examines changes in the relative importance of the different sources over time. The data indicate that...

Relative importance of sectoral and aggregate sources of price changes

This paper estimates a dynamic common factor model to assess relative importance of the aggregate and the sector-specific factors that determine changes in the prices of individual products. It also examines how aggregate price changes are affected by these factors. Two different specifications of the model are estimated: the baseline model with one aggregate factor, and a second specification ...