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Fresh produce can become contaminated with disease‐causing microorganisms and chemical contaminants at every step of the production and processing chain and in a variety of ways, including through contact with contaminated process water. Water quality is critical to prevent microbial and chemical risks in any of the postharvest and processing operations related to fresh and fresh‐cut fruits and vegetables. The wash process requires high volumes of water, which are usually reduced by water reuse. To maintain the microbiological quality of the process water, intervention strategies are needed. Chemical disinfection is the most common method to maintain the microbial quality of process water. However, the use of chemicals leads to the formation/accumulation of disinfection byproducts (DBPs), which can be absorbed by the washed vegetables. This is the case of trihalomethanes (THMs) and chlorates. The presence of high concentrations of DBPs in vegetables has led to an intensive debate on current disinfection practices and how DBPs may enter the food supply chain, becoming a potential health risk for consumers. To assess the risk associated with the formation/accumulation of DBPs in process water, a quantitative analysis was done. Available data have been used to develop mathematical models to predict the formation/accumulation of DBPs (chlorates and THMs) in process water due to the use of chlorine‐derived compounds. Preliminary models have been developed, but adjustments are still needed to refine them. The present study contributes more information related to the development of a mathematical model for the accumulation of chlorates and THMs in process water.

Atlantic and Mediterranean warming-related diseases outbreaks and species shifts recently have been documented. Evaluated tools of short-term effects on the health or organisms resistance are necessary to assess and understand mechanisms affecting marine biodiversity. Until now, climate warming has been studied at the population or community level. Here we offer a better understanding of such phenomena at the individual organism level, using anatomic-morphological approaches to interpret effects of natural physical stressors, according to behavioral patterns. The goal of this work was to evaluate the sea anemones behavior with temperature variance. This study takes a method of behavioral observations (morphological and anatomic parameters, with physiological implications) to identify changes in behavior, after exposure to the physical stressors temperature (10˚C, 15˚C, 20˚C, 25˚C and 30˚C) on temperate sea anemone Actinia equina over 96 h of exposure. Other endpoints as condition index and reproduction also assessed. Behavioral patterns analysis placed the differentially ecological functions in a wide range of categories including tentacle flexion, tentacle retraction, column cavitation, peristome depression and oral disc flexion. These parameters suggest that the "early stress response" (before result on individual death) to elevated temperature involves essentially all aspects of same chemical reactions. In this case we observed receptors functioning and the frequency of open-close oral sea anemones, tentacles and columns anatomic alterations to detect earlier the efHow to cite this paper: Gadelha, J.R., Jesus, F., Gomes, P.B., Von Osten, J.R., Morgado, 2/24OALib Journal fects of physical stress induction. The superiority of results tested was that the key species reacted to different temperature ranges in order to demonstrate that species from different climatic zones could have the same behavioral pattern but have intrinsic adaptations on each climatic zone. Also some collections of parameters such as: 1) water nutrients availability, 2) reproductions rate (number of polyps), 3) survival (condition index) and 4) temperature variations were significant on behavioral answers.

Zinc is a trace metal that is regularly found at pollution sites, amongst other metals and pollutants, contributing to the toxicity of marine ecosystems. In this study zinc acute toxicity tests were conducted on the sea anemone Actinia equina. This sea anemone presents a wide geographic distribution on rocky shore marine habitats, is quite resistant to some degree of various forms of contaminants and plays an important ecological key role in the marine environments.After a period of acclimatising on a flow through system, organisms of the same average size were exposed to different concentrations of zinc solution during a period of 96 hours (0 µg/l, 10 µg/l, 50 µg/l, 100 µg/l, and 200µg/l). The histological processing of the specimens was performed using standard procedures, slightly modified due to the peculiar nature of the biological material.The general effects exhibited necrosis of tentacles, mesenterial filaments, and in the gastrodermal regions (Figures 1, 2 and 3). It were observed tentacular cysts, black particulate accumulations in the gastrodermis, hypertrophied cells in the lobes of the mesenteries filaments, and spirocyst and associated necrosis (Fig. 2-3). All anemones exhibited extensive areas of tissue necrosis, degeneration of the epidermis in various stages, with loss of mucous cells, vacuolation, necrosis and ptychocysts from the epidermis, necrosis of retractor muscles and ducts (Figures 2-3). Neoplasms of the gastrointestinal tract and gonads were observed in internal structures. In the former, modifications of the mesenteries such as intensive fragmentation, vacuolization and epithelial thinning and in the latter abnormal gonad development and necrosis were noted (Figures 2-3).The data suggests that Actinia equina may be adversely affected by acute exposures to high levels of zinc as seen during laboratory exposures of other invertebrates and is also probably sensitive to acute exposures to metal’s toxic sediments in the marine environment. The loss of mucous secretory cells and ptychocysts from the epidermis suggest that energy reserves for cell replenishment were adversely affected. Mucus production in benthic cnidarians is necessary to prevent burial by sedimentation and to protect against toxins or invading microorganisms. The serious effects on the gastrodermis integrity indicate that sea water in the coelenteron is no longer circulated. The observed modifications could be considered as a general cnidarians response to stress.Further investigations of bioaccumulation, physiology, and histopathology in this anemone and other anthozoans from polluted environments should prove to be valuable in pollution monitoring studies, as they have for other benthic invertebratesAcknowledgmentsThis work was supported by the Portuguese Foundation for the Science and Technology – Portugal and FEDER funds, through the Projects: PTDC/MAR/464729/2006 and FCT/CNPq (Brazil), Project 6818, Programme 19/ 004.