<sup>14</sup>C‐MIB adsorption on PAC in natural water

Gillogly, Thomas E.T.; Snoeyink, Vernon L.; Elarde, Joseph R.; Wilson, Claude; Royal, Earl P.

doi:10.1002/j.1551-8833.1998.tb08364.x

“…Because of its ease of analysis and the small sample volume required, 14 C‐labeled MIB ( 14 C‐MIB)* was used. Analysis of 14 C‐MIB samples 22 yielded a 3.0‐ng/L detection limit.…”

Section: Methodsmentioning

confidence: 99%

Determining GAC bed life

Gillogly¹,

Snoeyink²,

Vogel³

et al. 1999

Self Cite

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Laboratory columns closely simulated the performance of a pilot plant for taste and odor control. This study developed a way to rapidly and effectively evaluate the remaining life of a granular activated carbon (GAC) bed used to mitigate taste and odor episodes. The maximum attenuation of a 2‐methylisoborneol (MIB) episode, a representative taste and odor compound, can rapidly be determined using laboratory‐scale columns packed with partially spent GAC taken from full‐scale operating adsorbers. These laboratory‐scale columns closely simulated the performance of pilot‐scale columns. The percent of a transient MIB load removed by GAC did not depend on the influent MIB concentration but did depend on the amount of natural organic matter adsorbed on the GAC surface. This approach can be used to determine GAC's potential percentage removal of taste‐ and odor‐causing compounds as a function of GAC service time. It allows GAC to be tested to estimate its readiness for summer taste and odor episodes. Adsorption alone in GAC adsorbers that used < 10 min of empty bed contact time was insufficient to fully protect against typical MIB episodes.

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“…Usually, 1 to 3 h of contact is provided for the PAC, after which the PAC settles out in the sedimentation tank, and is then disposed with other WTP sludges. For example, PAC added at dosages ranging from 5 to 50 mg/L removed greater than 90% of methylisoborneol (Log K OW 5 3.1) in raw water (Gillogly et al, 1998;Zhang and Emary, 1999;Bruce et al, 2002). Under the conditions encountered in drinking water treatment plants, removal of micropollutants by PAC tends to be independent of initial contaminant concentrations (Knappe et al, 1998;Leung and Segar, 1999).…”

Section: Implications For the Water Industry 457mentioning

confidence: 99%

Pharmaceuticals, Personal Care Products, and Endocrine Disruptors in Water: Implications for the Water Industry

Snyder¹,

Westerhoff²,

Yoon³

et al. 2003

Environmental Engineering Science

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For over 70 years, scientists have reported that certain synthetic and natural compounds could mimic natural hormones in the endocrine systems of animals. These substances are now collectively known as endocrine-disrupting compounds (EDCs), and have been linked to a variety of adverse effects in both humans and wildlife. More recently, pharmaceuticals and personal care products (PPCPs) have been discovered in various surface and ground waters, some of which have been linked to ecological impacts at trace concentrations. The majority of EDCs and PPCPs are more polar than traditional contaminants and several have acidic or basic functional groups. These properties, coupled with occurrence at trace levels (i.e., ,1 mg/L), create unique challenges for both removal processes and analytical detection. Reports of EDCs and PPCPs in water have raised substantial concern among the public and regulatory agencies; however, very little is known about the fate of these compounds during drinking and wastewater treatment. Numerous studies have shown that conventional drinking and wastewater treatment plants can not completely remove many EDCs and PPCPs. Oxidation with chlorine and ozone can result in transformation of some compounds with reactive functional groups under the conditions employed in water and wastewater treatment plants. Advanced treatment technologies, such as activated carbon and reverse osmosis, appear viable for the removal of many trace contaminants including EDCs and PPCPs. Future research needs include more detailed fate and transport data, standardized analytical methodology, predictive models, removal kinetics, and determination of the toxicological relevance of trace levels of EDCs and PPCPs in water.Key words: endocrine disruptor; pharmaceutical; drinking water; wastewater; treatment; review 449 ENDOCRINE DISRUPTING COMPOUNDS P ERHAPS THE MOST DIFFICULT PART of understanding the subject of endocrine disruption involves a definition of the term. The Environmental Protection Agency (EPA) has defined environmental endocrine disrupting compounds (EDCs) as exogenous agents that interfere with the "synthesis, secretion, transport, binding, action, or elimi- nation of natural hormones in the body that are responsible for the maintenance of homeostasis, reproduction, development, and/or behavior" (EPA, 1997). However, definitions and opinions on what defines an EDC vary greatly. It is generally accepted that the three major classes of endocrine disruption endpoints are estrogenic (compounds that mimic or block natural estrogen), androgenic (compounds that mimic or block natural testosterone), and thyroidal (compounds with direct or indirect impacts to the thyroid). As we will illustrate, the majority of research thus far has focused only on estrogenic compounds; however, disruption of androgen and thyroid function may be of greater or equal importance biologically.Although the topic of endocrine disruption is considered an "emerging issue" in the water industry, scientists have known about the ability o...

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“…Usually, one to three hours of contact is provided for the PAC, after which the PAC settles out in the sedimentation tank, and is then disposed with other WTP sludges. For example, PAC added at dosages ranging from 5 to 50 mg/L removed greater than 90% of methylisoborneol (MIB; Log KOW = 3.1) in raw water (Bruce et al, 2002;Gillogly et al, 1998;Zhang and Emary, 1999). Under the conditions encountered in drinking water treatment plants, removal of micropollutants by PAC tends to be independent of initial concentrations (Knappe et al, 1998;Leung and Segar, 1999).…”

Section: Activated Carbon Adsorptionmentioning

confidence: 95%

Endocrine Disruptors and Pharmaceuticals: Implications for the Water Industry

Snyder¹,

Westerhoff²,

Wert³

et al. 2005

proc water environ fed

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For over 70 years, scientists have reported that certain synthetic and natural compounds could mimic natural hormones in the endocrine systems of animals. These substances are now collectively known as endocrine-disrupting compounds (EDCs) and have been implicated in variety of adverse effects in both humans and wildlife. More recently, pharmaceuticals and personal care products (PPCPs) have been discovered in various surface and ground waters, some of which have been linked to ecological impacts at trace concentrations. The majority of EDCs and PPCPs are more polar than traditional contaminants and several have acidic or basic functional groups. These properties, coupled with occurrence at trace levels (i.e., < 1 µg/L), create unique challenges for both removal processes and analytical detection. Reports of EDCs and PPCPs in water have raised substantial concern among the public and regulatory agencies; however, very little is known about the fate of these compounds during drinking and wastewater treatment. Numerous studies have shown that conventional drinking and wastewater treatment plants do not completely remove many EDCs and PPCPs. Oxidation with chlorine and ozone can result in transformation of some compounds with reactive functional groups under the conditions employed in water and wastewater treatment plants. Advanced treatment technologies, such as activated carbon and reverse osmosis, appear viable for the removal of many trace contaminants including EDCs and PPCPs. Since modern analytical methods are capable detecting miniscule levels of contaminants, no treatment technology can truly removal all compounds to below detection. More research is needed to determine the levels of these contaminants that induce toxicological impacts in order to establish reasonable treatment goals.

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¹⁴C‐MIB adsorption on PAC in natural water

Cited by 61 publications

References 14 publications

Determining GAC bed life

Determining GAC bed life

Pharmaceuticals, Personal Care Products, and Endocrine Disruptors in Water: Implications for the Water Industry

Endocrine Disruptors and Pharmaceuticals: Implications for the Water Industry

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14C‐MIB adsorption on PAC in natural water

Cited by 61 publications

References 14 publications

Determining GAC bed life

Determining GAC bed life

Pharmaceuticals, Personal Care Products, and Endocrine Disruptors in Water: Implications for the Water Industry

Endocrine Disruptors and Pharmaceuticals: Implications for the Water Industry

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¹⁴C‐MIB adsorption on PAC in natural water