## 4 Discussion  
Based on the types of produce crop irrigation examined in this study using NC Type 2 reclaimed water, it was found that the annual risk of infection is not always reduced below the acceptable DALY risk level of \(<\)1 \(\times\) 10\({}^{-6}\). Based on this analysis of North Carolina Type 2 reclaimed water, for all irrigation types, the risks of viral infection by adenoviruses groups A-F were lower than the acceptable risk level; however, for _Salmonella_ spp., _Cryptsporidium_, and _Giardia_, the annual risk of infection was sometimes higher than is considered acceptable. Potential reasons for the higher level of risks for bacteria and protozoan parasites include increased survival on plant surfaces after irrigation, as well as a difference in the volume of water retained on the produce after irrigation. Sensitivity analyses indicated that the pathogen concentration in reclaimed water played the largest role in the pathogen risk differences. Previous researchers [7, 18, 29] have evaluated reclaimed water for agricultural purposes and have compared the risks from these exposures to benchmarks set for drinking water risks (10\({}^{-4}\) infections per year); in this study, the reclaimed water proposed for agricultural reuse in NC was compared to the globally used WHO targets for reuse applications. [PERSON] and [PERSON], 2010, found that the estimated average annual risk of infection from SI was 10\({}^{-6}\), and the infection risks from DI and SDI were 10\({}^{-8}\) and 10\({}^{-9}\), respectively [18]. [PERSON] et al. (2005), using secondary effluent water, also found a similar risk of virus infections modeled using coliphage virus (fecal indicator viruses infecting _E. coli_ bacteria) data on different types of vegetables when a 14-day period was considered between irrigation and consumption, with average annual risks ranging from 10\({}^{-5}\) for lettuce, to 10\({}^{-7}\) for cucumber and broccoli [7]. [PERSON] et al. (2015) evaluated the average annual risks of infection for _Salmonella_ and found that these risks (on average between 10\({}^{-2}\) to 10\({}^{-3}\) per year) were higher than those of viral infection [29]. These values for _Salmonella_ spp. are within the estimated ranges of average annual risks obtained in this present study. The risk of _Cryptsporidium_ in irrigation waters was evaluated by [30, 31]. [PERSON] et al. (2009) found that, assuming 120 days of exposure per year, the annual risks of _Cryptsporidium_ infection for tomatoes, bell peppers and cucumbers were all approximately 10\({}^{-5}\)[30]. The discrepancies between this value and the risks reported by our study could be a result of the shorter period of exposure of the reclaimed to fresh produce. [PERSON] et al. (2012) found average annual risk levels of 4.37 \(\times\) 10\({}^{-2}\) in tertiary treated effluent for total _Cryptsporidium_ (not infectiousocysts) [31]. From our research, the DALYs for illness from exposure to agricultural reuse waters were reduced below the WHO proposed DALY level for all irrigation methods, with the exception of SI. As it is not clear if the _Cryptsporidium_ oocysts evaluated in this study were infectious, further study is needed to evaluate the infectivity of human infectious _Cryptsporidium_ parasites after tertiary wastewater and then UV treatment. If UV treatment reduces the infectivity of the _Cryptsporidium_ oocysts, the health risks would be lower than those calculated here. Although infectivity data are possible to obtain for _Cryptsporidium_ using a cell culture infectivity assay system, little information is available on _Giardia intestinalis_ infectivity due to the lack of a cell culture infectivity system. Therefore, the resulting annual risks of giardiasis are uncertain due to the lack of cyst infectivity data. In a recent examination of the survival of adenoviruses and norovirus GII, [PERSON] et al. (2021) found that the number of viruses were not significantly reduced by UV and chlorine dual disinfection treatment, which is consistent with our study for adenoviruses [32].