LexaMed has a comprehensive water treatment system to control the quality of water utilized in its laboratory operation located at 705 Front Street, Toledo, Ohio.
The System was designed and installed by Evoqua Water Technologies LLC (formally Siemens). The system consists of the following basic elements:
• 10”, 5 micron prefilter for the chlorinated city of Toledo source water
• 1.2 cubic foot carbon bed
• 1.2 cubic foot cation bed deionization tank
• 1.2 cubic foot anion bed deionization tank
• (2) 1.2 cubic foot mixed bed deionization tanks
• UV unit
• 9.75”. 0.2 micron bacterial filter
• 20”, 0.05 micron hollow filter Ultra Filter for endotoxin, bacterial and fine particle removal (FiberFlo HF 50-203, Minntech Therapeutic Technologies)
• Recirculation pump to maintain system in constant movement through the tanks, filters and UV
To assure the continued effectiveness of the system, LexaMed has a service contract with Evoqua Water Technologies for routine maintenance of the system, including changing out the deionization tanks as required, changing the filters and sanitizing the ultra-filter. LexaMed also routinely tests the water for endotoxins, microbial contamination, TOC (total organic carbon) and conductivity. Trending data has demonstrated that the system has been fundamentally stable and in control since the addition of the ultra –filter in August 2011.
LexaMed receives it’s water from the city of Toledo. On Saturday morning, August 2, 2014 the city issued a prophylactic warning, concerning its potable water supply over a concern for the presence of a toxin related to bacterial growth in Lake Erie, the source of Toledo’s drinking water. Routine testing conducted by the city indicated a level of the toxin which exceeded the WHO (World Health Organization) threshold level of 1 ug/l. The toxin is known as microcystin and is produced by strains of Cyanobacterium, also known as blue-green algae. Microcystins are not regulated by the US EPA. Studies indicate that ~ 80% of water samples tested in the US and Canada were positive for the presence of microcystins and 4.3% had levels exceeding the WHO threshold level of 1 ug/l. On-going testing conducted by the City of Toledo indicated the level of microcystins in the water had returned to a concentration below the threshold level by August 4, 2014. During this time period no testing was conducted by LexaMed, therefore no studies were impacted by this excursion.
The EPA website lists treatment procedures that are known to be effective in the removal of microcystins (http://iaspub.epa.gov/tdb/pages/contaminant/treatmentSummary); several of these control procedures are incorporated into the LexaMed water system. These include an activated carbon filter, UV irradiation, and a 0.05µm porosity hollow-fiber ultra-filter. The LexaMed water system, therefore, integrates design features that are reported to control microcystin levels. Based on this design, it is our belief that the cumulative effect of these control features will routinely result in water meeting the quality requirements of our laboratory operation.