Richard P. Maas

Reducing Lead Exposure from Drinking Water: Recent History and Current Status

This article discusses the issue of lead contamination of drinking water, noting the various regulatory-driven measures that have been adopted in the U.S. since 1986 to address this public health issue. The article summarizes the literature on the dynamics of tap water lead contamination and discusses this widespread source of lead exposure in the context of the latest research evidence.

The Dynamics of Lead in Drinking Water in U.S. Workplaces and Schools

A statistical analysis of water samples from over 12,000 school and workplace water coolers, bubblers, chillers, faucets, and ice makers determined that there is a substantial risk of excessive lead concentrations in first-draw water from sources of all types. Of all sources tested, 17.2% had lead concentrations in excess of 15 ppb. A comparison of lead concentrations by brand of water cooler was made for all manufacturers for which at least 50 samples were available. The percentage of water sources with first-draw lead concentrations above 15 ppb was reduced by 58%-84% by flushing the source prior to use. Special attention was given to determining the relationships between lead levels and factors such as water pH, water cooler age, and line purging. While each of these variables was found to be statistically significant, the overwhelming indication of this research is that testing individual water sources is apparently the only reliable way to determine whether a lead contamination problem exists.

Developing a Rigorous Water Quality Database Through a Volunteer Monitoring Network

ABSTRACT Lake and reservoir managers, as well as affected citizen groups, have increasingly recognized the need for extensive watershed-level land use and water quality data in developing effective lake management strategies. Water quality data, in particular, from lake or reservoir tributaries is essential for identifying and quantifying point and nonpoint sources of pollutants. The realization of these informational needs, coupled with the personnel and financial resource constraints that limit most governmental agency monitoring programs, have helped to spawn a multitude of citizen-organized volunteer water quality monitoring programs. This paper describes a unique volunteer-based monitoring network, which in cooperation with a university laboratory, is developing laboratory monitoring data using EPA-certified methods at minimal cost. The program consists of 45 stream sites, each of which is staffed by two or more volunteers. The network is sampled monthly for 12 parameters including various nutrients ...

A pilot simulation study of arsenic tracked from CCA-treated decks onto carpets

A controlled simulation experiment was performed to assess whether dislodgeable arsenic can be tracked onto carpets via foot traffic from chromated copper arsenate (CCA) pressure-treated decks. The pilot simulation study demonstrated that it is possible to track arsenic from CCA-decks onto carpets under the test conditions evaluated. A total of nine CCA-decks and two non-CCA-treated control surfaces were tested under wet and dry conditions. Five participants walked in a controlled manner (60 cycles, 11 steps per cycle) across decks and then walked over various lanes of carpet to simulate the tracking of arsenic indoors on the bottoms of shoes under heavy foot traffic conditions. To determine if arsenic was transferred from the CCA-treated wood to the carpet via shoes, laboratory analysis was performed on three different types of samples: (1) wipe samples of dislodgeable arsenic from a 46 cm(2) area of carpet, (2) dust samples obtained from vacuuming a 7442 cm(2) area of carpet, and (3) extractions of 13 cm(2) carpet samples. Wipe samples were also taken directly from the deck lumber. Following digestion and extraction, the amount of arsenic in each sample was measured using Graphite Furnace Atomic Absorption Spectrometry. The mean arsenic concentration measured on the carpets was 2.52 microg/(100 cm(2)) and 2.05 microg/(100 cm(2)) with wipes for the dry and wet conditions, respectively, 4.69 microg/(100 cm(2)) and 0.68 microg/(100 cm(2)) with vacuumed dust for the dry and wet conditions, respectively, and 15.56 microg/(100 cm(2)) and 12.31 microg/(100 cm(2)) with carpet extractions for the dry and wet conditions, respectively. The mean arsenic concentration measured on the decks was 22.2 microg/(100 cm(2)) with wipes. Further research is needed to determine if indoor exposure to arsenic due to track-in from outdoor decks via foot traffic is significant compared to exposures from other sources.

An Educational Program for Farmers on Preventing Lake Contamination from Agricultural Pesticides

ABSTRACT Pesticides continue to be one of the major causes of fishkills in the United States, and can contaminate surface and ground water supplies that provide drinking water for animal and human populations. During the past 10 years a wealth of research data has been amassed on the aquatic transport properties of various pesticides and pesticide classes. However, there has been a serious dearth of practical information for agricultural pesticide applicators to use to avoid surface and groundwater contamination. This paper describes the components of a successful preventive program for pesticide management that integrates production agriculture and water quality concerns. This educational program has been extensively reviewed by county agricultural agents and soil and water conservation field personnel in North Carolina and is now increasingly being distributed nationally.