Chemical, microbial and physical evaluation of commercial bottled waters in greater Houston area of Texas

Bottled water contaminant exposures and potential human effects

BACKGROUND

Bottled water (BW) consumption in the United States and globally has increased amidst heightened concern about environmental contaminant exposures and health risks in drinking water supplies, despite a paucity of directly comparable, environmentally-relevant contaminant exposure data for BW. This study provides insight into exposures and cumulative risks to human health from inorganic/organic/microbial contaminants in BW.

METHODS

BW from 30 total domestic US (23) and imported (7) sources, including purified tapwater (7) and spring water (23), were analyzed for 3 field parameters, 53 inorganics, 465 organics, 14 microbial metrics, and in vitro estrogen receptor (ER) bioactivity. Health-benchmark-weighted cumulative hazard indices and ratios of organic-contaminant in vitro exposure-activity cutoffs were assessed for detected regulated and unregulated inorganic and organic contaminants.

RESULTS

48 inorganics and 45 organics were detected in sampled BW. No enforceable chemical quality standards were exceeded, but several inorganic and organic contaminants with maximum contaminant level goal(s) (MCLG) of zero (no known safe level of exposure to vulnerable sub-populations) were detected. Among these, arsenic, lead, and uranium were detected in 67 %, 17 %, and 57 % of BW, respectively, almost exclusively in spring-sourced samples not treated by advanced filtration. Organic MCLG exceedances included frequent detections of disinfection byproducts (DBP) in tapwater-sourced BW and sporadic detections of DBP and volatile organic chemicals in BW sourced from tapwater and springs. Precautionary health-based screening levels were exceeded frequently and attributed primarily to DBP in tapwater-sourced BW and co-occurring inorganic and organic contaminants in spring-sourced BW.

CONCLUSION

The results indicate that simultaneous exposures to multiple drinking-water contaminants of potential human-health concern are common in BW. Improved understandings of human exposures based on more environmentally realistic and directly comparable point-of-use exposure characterizations, like this BW study, are essential to public health because drinking water is a biological necessity and, consequently, a high-vulnerability vector for human contaminant exposures.

Evaluation of occurrence of organic, inorganic, and microbial contaminants in bottled drinking water and comparison with international guidelines: a worldwide review

The aim of this study was to evaluate the levels of inorganic and organic substances as well as microbial contaminants in bottled drinking water on a global scale. The findings were compared to WHO guidelines, EPA standards, European Union (EU) directive, and standards drafted by International Bottled Water Association (IBWA). Our review showed that 46% of studies focused on the organic contaminants, 25% on physicochemical parameters, 12% on trace elements, 7% on the microbial quality, and 10% on microplastics (MPs) and radionuclides elements. Overall, from the 54 studies focusing on organic contaminants (OCs) compounds, 11% of studies had higher OCs concentrations than the standard permissible limit. According to the obtained results from this review, several OCs, inorganic contaminants (IOCs), including CHCl3, CHBrCl2, DEHP, benzene, styrene, Ba, As, Hg, pb, Ag, F, NO3, and SO4 in bottled drinking water of some countries were higher than the international guidelines values that may cause risks for human health in a long period of time. Furthermore, some problematic contaminants with known or unknown health effects such as EDCs, DBP, AA, MPs, and some radionuclides (40K and 222Rn) lack maximum permissible values in bottled drinking water as stipulated by international guidelines. The risk index (HI) for OCs and IOCs (CHBrCl2, Ba, As, and Hg) was higher than 1 in adults and children, and the value of HI for CHCl3 in children was more than 1. Thus, further studies are required to have a better understanding of all contaminants levels in bottled drinking water.

Heavy metal concentrations in rivers and drinking water of Esmeraldas (Ecuador) under an intermittent water supply service

Universal access to safe water is a major global goal, but these efforts could be at stake because drinking water sources are becoming polluted in many developing countries. Chlorine, major ions, and heavy metals were measured in rivers and drinking water of Esmeraldas because potential pollution sources raise concerns about the quality of the water supply, and because users have developed strategies to cope with water shortages including collecting river water and water distributed by tankers, storing water at home, and consuming commercial bottled water. We sampled water from the water distribution system (WDS) and the Esmeraldas and Teaone rivers including the intake to the potabilization plant, water distributed by tankers, and commercial bottled water. Most of the samples collected from the Esmeraldas and Teaone rivers, the WDS, and tankers complied with drinking water standards, but higher concentration of cadmium and other metals in the eastern part of the city is an indication of corrosion inside the WDS. Commercial bottled and WDS water showed similar heavy metal concentrations, but regular consumption of some brands may lead to higher exposure to arsenic and mineral deficiencies. Chlorine concentrations in the water supplied by the WDS were below the values required for safe disinfection, and in-house chlorination is uncommon in the city. Strengthening pollution control in the Esmeraldas river, monitoring corrosion of the WDS, and promoting point-use chlorination and better water handling practices are required to secure a safer water supply in the long term.

In vitro Approaches to Support Bioequivalence and Substitutability of Generic Proton Pump Inhibitors via Nasogastric Tube Administration

Administration of proton pump inhibitors (PPIs) through nasogastric tubes may present risks. If the PPI drug products are not prepared properly, clogging or obstruction of nasogastric tubes can pose a safety concern. In addition, the integrity of the enteric coating of the drug product may be damaged resulting in reduced bioavailability of the active moiety. From the perspective of administration of generic PPIs when compared to the reference drug product, differences in formulation can potentially result in a greater relative risk for the generic drug product. As part of the assessment of bioequivalence, the Office of Generic Drugs (OGD) has developed a suite of in vitro testing to compare the delivery of the generic and reference products via nasogastric tubes. These in vitro tests assess essential attributes associated with the likelihood of clogging and maintenance of the enteric coating. These in vitro tests include studies evaluating sedimentation, granule size distribution, drug recovery, and acid resistance. One of the challenges is that while the administration of PPIs through nasogastric tubes is common in clinical practice, this issue is not uniformly addressed in the FDA approved label of the reference drug products. This paper discusses the design and rationale for in vitro testing of PPI formulations with respect to bioequivalence via nasogastric tube administration and in addition, it summarizes commonly occurring deficiencies in the in vitro nasogastric tube testing of 14 recent Abbreviated New Drug Applications (ANDA) submitted for five generic PPI drug products.

Physicochemical properties of some bottled water brands in Alexandria Governorate, Egypt

BACKGROUND

Many people use bottled water instead of tap water for many reasons such as taste, ease of carrying, and thinking that it is safer than tap water. Irrespective of the reason, bottled water consumption has been steadily growing in the world for the past 30 years. In Egypt, this is still increasing to reach 3.8 l/person/day, despite its high price compared with tap water.

OBJECTIVE

The purpose of this study was to evaluate the physicochemical quality of some bottled water brands and to compare the quality with that reported on manufacture's labeling, Egyptian, and International standards.

MATERIALS AND METHODS

Fourteen bottled water brands were selected from the local markets of Alexandria city. Three bottles from each brand were randomly sampled, making a total sample size of 42 bottles. Sampling occurred between July 2012 and September 2012. Each bottle was analyzed for its physicochemical parameter and the average was calculated for each brand. The results obtained were compared with the Egyptian standard for bottled water, Food and Drug Administration (FDA), and with bottled water labels.

RESULTS

In all bottles in the study, pH values ranged between 7.21 and 8.23, conductivity ranged between 195 and 675 μs/cm, and total dissolved solids, sulfate, chloride, and fluoride were within the range specified by the FDA. Calcium concentrations ranged between 2.7373 and 29.2183 mg/l, magnesium concentrations ranged between 5.7886 and 17.6633 mg/l, sodium between 14.5 and 205.8 mg/l, and potassium between 6.5 and 29.8 mg/l. For heavy metals such as iron, zinc, copper, and manganese, all of them were in conformity with the Egyptian standards and FDA, but nickel concentration in 11 brands was higher than the Egyptian standards. Twelve brands were higher than the Egyptian standards in cadmium concentration, but on comparison with FDA there were only five brands exceeding limits. Lead concentrations were out of range for all brands. On comparison with the labeled values, the quality of bottled water was not complying with labeled values.

CONCLUSION

Physicochemical parameters in all bottled water examined brands were consistent with the Egyptian Standard and FDA, except for total dissolved solids, nickel, cadmium, and lead. Statistical analysis showed that there was significant difference (P<0.05) in all parameters tested between different brands. Values on the bottled water labels were not in agreement with analytical results.

Impact of temperature and storage duration on the chemical and odor quality of military packaged water in polyethylene terephthalate bottles

The impact of temperature and storage time on military packaged water (MPW) quality was examined at four temperatures (23.0 °C to 60.0 °C) for 120 days. Polyethylene terephthalate (PET) bottles were filled in California and Afghanistan with unbuffered water treated by reverse osmosis. The US military's water pH long-term potability standard was exceeded, and US Food and Drug Administration (USFDA) and US Environmental Protection Agency (USEPA) drinking water pH and odor intensity limits were also exceeded. During a 70 day exposure period, Port Hueneme MPW total organic carbon and total trihalomethane levels increased from < 0.25mg/L to 2.0 ± 0.0mg/L and <0.05 μg/L to 51.5 ± 2.1 μg/L, respectively. PET released organic contaminants into MPW and residual disinfectant generated trihalomethane contaminants. After 14 days at 37.7 °C and 60.0 °C, Afghanistan MPW threshold odor number values were 8.0 and 8.6, respectively. Total organic carbon concentration only increased with exposure duration at 60.0 °C. Acetaldehyde and formaldehyde contaminants were not detected likely due to the high method detection limits applied in this study. Phthalate contaminants detected and their maximum levels were butylbenzylphthalate (BBP) 0.43 μg/L, di-n-butylphthalate (DnBP) 0.38 μg/L, di(2-ethylhexyl)phthalate (DEHP) 0.6 μg/L, and diethylphthalate (DEP) 0.32 μg/L. Antimony was only detected in 60.0 °C Afghanistan MPW on Day 28 and beyond, and its maximum concentration was 3.6 ± 0.3 μg/L. No antimony was found in bottles exposed to lesser temperatures. Environmental health, PET synthesis and bottle manufacturers, and bottle users can integrate results of this work to improve health protective decisions and doctrine.

Impact of bottled water storage duration and location on bacteriological quality

An investigation studying the effects of storage duration and location on the persistence of heterotrophic microorganisms in oligotrophic bottled water environments has been completed. One-gallon high-density polyethylene water containers stored for up to 16 weeks at temperatures ranging from 2°C to >49°C in a refrigerator, indoor cabinet, covered porch, and car trunk were evaluated for microbiological quality. Heterotrophic plate counts (HPCs) of up to 4 × 10(3) cfu/mL were detected in containers stored on a porch and car trunk; whereas, HPCs were found not to exceed 400 cfu/mL and 100 cfu/mL for bottles stored in indoor cabinets and refrigerators, respectively. Containers stored on an enclosed porch for up to seven years contained HPC of up to 4 × 10(4) cfu/mL. Logistic and Gompertz growth models predicted microbial growth rates for bottled water stored on a protected porch environment for long (R(2) 0.99) and short-term (R(2) 0.86) durations.

Mixing-induced aggregation and associated microstructures in the capillary flow

With a device that uses microscopic imaging as the signal detection method for online laser light scattering of solutions driven to flow in a capillary tube, we have found that mixing of a solution with water and vice versa induce large numbers of aggregates in the free flow stream. The degrees of aggregation as measured from the total number of aggregates and the corresponding light-scattering intensities are dependent on the species of the solution. This species dependence of the mixing aggregation in the capillary flow has the potential for the development of new protocols or even spectroscopic methods for the detection of solute molecules and the assessment of solution qualities. Furthermore, even with pure-distilled and de-ionized water in the steady-state capillary flow, there are still countable numbers of aggregates detectable in the free flow stream, although of extremely low concentration of an estimated value of no more than 10(-15) M .