Kvävehalt i mänskligt urin baserat på kosthållning : Påverkan på tillväxt av grönslick (Cladophora glomerata) samt förekomst av fytoplankton

Sammanfattning: The Baltic Sea is a brackish water that is severely affected by eutrophication. Anthropogenic (human) nitrogen emissions is a contributing factor leading to algal blooms and hypoxic and anoxic seabeds. Municipal wastewater treatment plants account for 27 percent of the nitrogen emissions into the Baltic Proper. According to an article published by Karlsson-Ottosson in the magazine Ny Teknik and the HAVET 2015/2016 report, the increased meat consumption causes difficulties for the sewage treatment plants to purify the nitrogen in the wastewater. This, according to the article and report mentioned, correlates with increased nitrogen emissions from the municipal wastewater treatment plants. The purpose of this study was to investigate if this observed correlation could be confirmed. This study has measured the nitrogen content of urine from participants (n=36) categorized by diet. The diet categories that was included in this study were meat (K), lacto-ovo vegetarian (LOV) and vegan (V). The daily protein intake from the participants in the categories mentioned above was analyzed in this study. Furthermore, the growth of green algae (Cladophora glomerata) and presence of phytoplankton was investigated by fertilizing the collected samples with urine. The results show that there is no difference in nitrogen content in urine, neither in the protein intake between the three diet categories, nor in the case of presence of phytoplankton. Regarding the growth of the green algae, there was a significant difference between the diet groups of meat (K) and control (KON), and also between meat (K) and people on a vegan diet (V). The green algae therefore grew better in brackish water with urine from people who had a meat (K) diet than it did in brackish water with urine from people who had a vegan (V) diet. Though the growth results showed a significant difference between these diet groups (K and V), the alleged correlation between increasing meat consumption and increasing nitrogen emissions from municipal wastewater treatment plants needs to be further studied.