<\/p>\n
V\u00a0minul\u00e9m \u010d\u00edsle \u010dasopisu VTEI (5\/2016) se \u010dten\u00e1\u0159 mohl sezn\u00e1mit s\u00a0n\u00e1zorem SOVAKu \u010cR na podporu \u201eco nejrychlej\u0161\u00edho \u00fapln\u00e9ho z\u00e1kazu pou\u017e\u00edv\u00e1n\u00ed glyfos\u00e1tu\u201c s\u00a0ohledem na mo\u017enou kontaminaci povrchov\u00fdch vod touto l\u00e1tkou (hlavn\u00ed l\u00e1tka tot\u00e1ln\u00edch herbicid\u016f typu roundup) a\u00a0jej\u00edmi rezidui. Jeliko\u017e v\u00a0p\u0159\u00edsp\u011bvku nebyly uvedeny v\u0161echny relevantn\u00ed informace, aby si mohl \u010dten\u00e1\u0159 utvo\u0159it na uvedenou problematiku vlastn\u00ed n\u00e1zor, dovolil jsem si veskrze negativn\u00ed vyzn\u011bn\u00ed p\u016fvodn\u00edho p\u0159\u00edsp\u011bvku uv\u00e9st na pravou m\u00edru.<\/p>\n
C\u00edlem tohoto p\u0159\u00edsp\u011bvku nen\u00ed obhajovat pou\u017eit\u00ed glyfos\u00e1tu, kter\u00fd je \u010dasto vyu\u017e\u00edv\u00e1n ve zbyte\u010dn\u00fdch, nadm\u011brn\u00fdch mno\u017estv\u00edch (nap\u0159.\u00a0k\u00a0desikaci sklizn\u011b), n\u00fdbr\u017e poskytnout z\u00e1kladn\u00ed fakta o\u00a0jeho mechanismu p\u016fsoben\u00ed a\u00a0p\u0159edstavit zobecn\u011bn\u00e9 z\u00e1v\u011bry v\u011bdeck\u00fdch studi\u00ed, kter\u00e9 potenci\u00e1ln\u00ed \u0161kodlivost glyfos\u00e1tu v\u016f\u010di \u010dlov\u011bku, \u017eivo\u010dich\u016fm a\u00a0vodn\u00edmu prost\u0159ed\u00ed v\u00a0posledn\u00edch 30 letech zkoumaly (glyfos\u00e1t byl objeven v\u00a0roce 1970). I\u00a0tak nebude snadn\u00e9 alespo\u0148 vyv\u00e1\u017eit p\u0159ev\u00e1\u017en\u011b negativn\u00ed dlouhodobou kampa\u0148, kter\u00e1 je v\u00a0podob\u011b popla\u0161n\u00e9 zpr\u00e1vy ohledn\u011b pou\u017e\u00edv\u00e1n\u00ed glyfos\u00e1tu bez ohledu na fakta v\u00a0posledn\u00edch letech sd\u011blovac\u00edmi prost\u0159edky \u0161\u00ed\u0159ena.<\/p>\n
Glyfos\u00e1t je bezbarv\u00e1 organick\u00e1, \u0161irokospektr\u00e1ln\u011b p\u016fsob\u00edc\u00ed herbicidn\u00ed l\u00e1tka na b\u00e1zi fosforu, kter\u00e1 efektivn\u011b \u00fa\u010dinkuje v\u016f\u010di rostlinn\u00fdm zelen\u00fdm pletiv\u016fm (byliny i\u00a0d\u0159eviny), v\u010detn\u011b mechorost\u016f a\u00a0zelen\u00fdch \u0159as. Jeho \u00fa\u010dinek spo\u010d\u00edv\u00e1 v\u00a0utlumen\u00ed funkce rostlinn\u00e9ho enzymu (je sou\u010d\u00e1st\u00ed genomu i\u00a0n\u011bkter\u00fdch mikroorganism\u016f, nikoliv savc\u016f), kter\u00fd umo\u017e\u0148uje synt\u00e9zu aminokyselin, pot\u0159ebn\u00fdch k\u00a0r\u016fstu a\u00a0fungov\u00e1n\u00ed rostliny [1]. Obecn\u00e9 z\u00e1v\u011bry, kter\u00e9 reprezentuj\u00ed statisticky v\u00fdznamn\u00fd soubor n\u011bkolika des\u00edtek studi\u00ed ze v\u0161ech v\u011bdn\u00edch obor\u016f, zab\u00fdvaj\u00edc\u00edch se p\u016fsoben\u00edm a\u00a0\u00fa\u010dinky glyfos\u00e1tu na organismy, dosud neprok\u00e1zaly akutn\u00ed nebo chronickou toxicitu glyfos\u00e1tu (v\u00a0maxim\u00e1ln\u00edch mno\u017estv\u00edch pou\u017e\u00edvan\u00fdch p\u0159i zem\u011bd\u011blsk\u00e9 produkci) na teplokrevn\u00e9 organismy, tedy v\u010detn\u011b \u010dlov\u011bka. K\u00a0t\u011bmto z\u00e1v\u011br\u016fm do\u0161ly nap\u0159.\u00a0Evropsk\u00e1 komise (29.\u00a0\u010dervna rozhodla o\u00a0do\u010dasn\u00e9m prodlou\u017een\u00ed pou\u017e\u00edv\u00e1n\u00ed chemick\u00fdch p\u0159\u00edpravk\u016f na b\u00e1zi glyfos\u00e1tu po dobu 18\u00a0m\u011bs\u00edc\u016f), n\u011bmeck\u00fd Feder\u00e1ln\u00ed institut pro hodnocen\u00ed rizik, Evropsk\u00fd \u00fa\u0159ad pro bezpe\u010dnost potravin, americk\u00fd \u00da\u0159ad pro ochranu \u017eivotn\u00edho prost\u0159ed\u00ed a\u00a0jin\u00e9.<\/p>\n
V\u00a0roce 2015 byl glyfos\u00e1t rozhodnut\u00edm Mezin\u00e1rodn\u00ed agentury pro v\u00fdzkum rakoviny (IACR) na z\u00e1klad\u011b v\u00fdsledk\u016f omezen\u00e9ho v\u00fdb\u011bru studi\u00ed za\u0159azen do kategorie seznamu l\u00e1tek 2A\u00a0jako potenci\u00e1ln\u00ed karcinogen. Na stejn\u00e9m seznamu je pro ilustraci \u010dten\u00e1\u0159e i\u00a0\u010derven\u00e9 maso a\u00a0pit\u00ed hork\u00fdch n\u00e1poj\u016f o\u00a0teplot\u011b v\u00edce ne\u017e 65\u2008\u00b0C (tedy i\u00a0k\u00e1vy a\u00a0\u010daje). I\u00a0selsk\u00fdm rozumem lze dovodit, \u017ee extr\u00e9mn\u00ed p\u0159\u00edjem jak\u00e9koliv l\u00e1tky, v\u010detn\u011b t\u011bch z\u00e1kladn\u00edch jako soli nebo cukru, je pro \u010dlov\u011bka ohro\u017euj\u00edc\u00ed, a\u00a0je proto \u010dasto d\u016fvodem, aby tyto l\u00e1tky byly na podobn\u00e9 seznamy za\u0159azeny. O\u00a0jejich benefitech se v\u0161ak v\u00a0souvislostech s\u00a0nimi nemluv\u00ed. Nap\u0159.\u00a0nejv\u011bt\u0161\u00edm benefitem glyfos\u00e1tu je dlouhodob\u00e1 udr\u017eitelnost zem\u011bd\u011blsk\u00e9 produkce v\u00a0p\u0159\u00edpad\u011b vyu\u017eit\u00ed geneticky upraven\u00fdch odr\u016fd obilovin a\u00a0kuku\u0159ice (GMO) odoln\u00fdch v\u016f\u010di glyfos\u00e1tu p\u0159i \u0161irokospektr\u00e1ln\u00ed likvidaci plevel\u016f (samotn\u00e1 problematika GMO nen\u00ed c\u00edlem p\u0159\u00edsp\u011bvku).<\/p>\n
V\u00a0p\u0159\u00edsp\u011bvku SOVAKu zm\u00edn\u011bn\u00e1 kontaminace povrchov\u00fdch vod je ve skute\u010dnosti v\u00fdznamn\u011b omezena v\u00fdraznou adsorpc\u00ed glyfos\u00e1tu na p\u016fdn\u00ed \u010d\u00e1stice, nav\u00edc SOVAKem prezentovan\u00e9 hodnoty v\u00a0povrchov\u00fdch vod\u00e1ch z\u00a0Belgie, Irska a\u00a0\u0160v\u00e9dska na \u00farovni 139\u2013370 \u00b5g\u00b7l-1<\/sup> jsou v\u00a0\u0159\u00e1dech, kter\u00e9 zcela jist\u011b nelze naz\u00fdvat jako z\u00e1va\u017en\u00e9. Velikost takov\u00e9ho mno\u017estv\u00ed lze srovnat nap\u0159.\u00a0s\u00a0nejvy\u0161\u0161\u00ed mezn\u00ed hodnotou pro koncentraci celkov\u00fdch kyanid\u016f v\u00a0pitn\u00e9 vod\u011b v\u00a0\u010cR, kter\u00e1 \u010din\u00ed 50 \u00b5g\u00b7l-1 <\/sup>[2] a\u00a0u\u00a0kter\u00fdch je narozd\u00edl od glyfos\u00e1tu akutn\u00ed toxicita prok\u00e1z\u00e1na a\u00a0v\u0161eobecn\u011b zn\u00e1ma. Nav\u00edc p\u0159\u00edsp\u011bvek neuv\u00e1d\u00ed, zda jde o\u00a0pr\u016fm\u011brnou, \u010di maxim\u00e1ln\u00ed zm\u011b\u0159enou koncentraci. Nejcitliv\u011bj\u0161\u00edmi nezelen\u00fdmi organismy na glyfos\u00e1t jsou ryby a\u00a0oboj\u017eiveln\u00edci, z\u00a0nich\u017e u\u00a0n\u011bkter\u00fdch druh\u016f byla zji\u0161t\u011bna tzv.\u00a0st\u0159edn\u00ed smrtn\u00e1 koncentrace 38\u201339\u2008mg\u00b7l-1<\/sup> (tj.\u00a0100\u00d7 v\u00edce ne\u017e uveden\u00e9 koncentrace ve vod\u00e1ch) p\u0159i expozici 24 a\u00a096\u00a0hodin [3, 4].<\/p>\n Jinou v\u011bc\u00ed je samotn\u00e9 pou\u017eit\u00ed surfaktant\u016f (sm\u00e1\u010dedel) v\u00a0herbicidech na b\u00e1zi glyfos\u00e1tu, usnad\u0148uj\u00edc\u00edch jeho pr\u016fnik do zelen\u00fdch pletiv. Tyto l\u00e1tky jsou skute\u010dn\u011b dr\u00e1\u017ediv\u00e9 a\u00a0mohou vyvol\u00e1vat nejen u\u00a0lid\u00ed, ale i\u00a0u\u00a0vodn\u00edch organism\u016f r\u016fzn\u00e9 alergick\u00e9 reakce. Velmi \u010dasto je v\u0161ak tento jejich potenci\u00e1ln\u00ed negativn\u00ed efekt zam\u011b\u0148ov\u00e1n pr\u00e1v\u011b s\u00a0glyfos\u00e1tem samotn\u00fdm (nap\u0159.\u00a0u\u00a0zm\u00edn\u011bn\u00fdch citliv\u00fdch oboj\u017eiveln\u00edk\u016f je st\u0159edn\u00ed smrtn\u00e1 koncentrace surfaktant\u016f 1,1\u2008mg\u00b7l-1<\/sup> p\u0159i expozici 24 a\u00a096\u00a0hodin, co\u017e je 35\u00d7 men\u0161\u00ed hodnota ne\u017e u\u00a0glyfos\u00e1tu). P\u0159itom vhodnou \u00fapravou legislativy lze pou\u017eit\u00ed surfaktant\u016f v\u00a0herbicidech \u00fa\u010dinn\u011b omezit. D\u00edl\u010d\u00edm probl\u00e9mem mohou b\u00fdt r\u016fzn\u00e1 rezidua, a\u00a0to jak ze surfaktant\u016f, tak z\u00a0glyfos\u00e1tu. Glyfos\u00e1t v\u00a0\u0159\u00e1du jednotek dn\u016f a\u017e m\u011bs\u00edc\u016f (podle charakteru prost\u0159ed\u00ed) biodegraduje p\u0159es meziprodukty a\u017e na kone\u010dn\u00e9 produkty v\u00a0podob\u011b CO2<\/sub> a\u00a0iont\u016f NH4<\/sub>+<\/sup> [4], co\u017e p\u0159i zv\u00fd\u0161en\u00e9 biochemick\u00e9 oxidaci (nitrifikaci) m\u016f\u017ee v\u00e9st a\u017e ke kysl\u00edkov\u00e9mu deficitu ve vodn\u00edm prost\u0159ed\u00ed. To plat\u00ed p\u0159edev\u0161\u00edm pro stojat\u00e9 vody, kde je nutn\u00e9 p\u0159i pou\u017eit\u00ed glyfos\u00e1tu v\u00a0jejich okol\u00ed s\u00a0t\u00edmto efektem po\u010d\u00edtat, ve vodn\u00edch toc\u00edch je obvykle areace vody dostate\u010dn\u00e1. Samotn\u00e9 meziprodukty \u010d\u00edtaj\u00ed r\u016fzn\u00e9 l\u00e1tky organick\u00e9 povahy od zcela netoxick\u00fdch (aminokyseliny) a\u017e po ty toxick\u00e9 (formaldehyd), nicm\u00e9n\u011b vych\u00e1z\u00edme\u00ad\u00ad\u2011li z\u00a0b\u011b\u017en\u00fdch koncentrac\u00ed glyfos\u00e1tu v\u00a0povrchov\u00fdch vod\u00e1ch, jsou jejich koncentrace enviroment\u00e1ln\u011b nev\u00fdznamn\u00e9.<\/p>\n V\u00fdsledky dosavadn\u00edho celosv\u011btov\u00e9ho sledov\u00e1n\u00ed vlivu glyfos\u00e1tu na zdrav\u00ed \u010dlov\u011bka z\u00a0hlediska konzumace glyfos\u00e1tem o\u0161et\u0159en\u00fdch potravin nebo pitn\u00e9 vody se stopami glyfos\u00e1tu zat\u00edm neprok\u00e1zaly jeho akutn\u00ed ani chronickou toxicitu v\u016f\u010di teplokrevn\u00fdm organism\u016fm v\u00a0koncentrac\u00edch, se kter\u00fdmi se v\u00a0prost\u0159ed\u00ed m\u016f\u017eeme b\u011b\u017en\u011b setkat. Neznamen\u00e1 to, \u017ee potenci\u00e1ln\u00ed toxick\u00e9 \u00fa\u010dinky glyfos\u00e1tu nemohou b\u00fdt dal\u0161\u00edm v\u00fdzkumem v\u00a0budoucnu objeveny, nicm\u00e9n\u011b je v\u00edce ne\u017e sporn\u00e9 vyvol\u00e1vat negativn\u00ed kampa\u0148 proti pou\u017e\u00edv\u00e1n\u00ed glyfos\u00e1tu na z\u00e1klad\u011b n\u011bkolika ojedin\u011bl\u00fdch v\u00fdsledk\u016f, t\u00edm sp\u00ed\u0161e nepodlo\u017een\u00fdch fakt\u016f a\u00a0domn\u011bnek. Pokud SOVAK hovo\u0159\u00ed o\u00a0probl\u00e9mech s\u00a0pesticidy na \u00fapravn\u00e1ch vod, je z\u00a0tohoto d\u016fvodu pon\u011bkud ne\u0161\u0165astn\u00e9 a\u00a0zav\u00e1d\u011bj\u00edc\u00ed uv\u00e1d\u011bt jako p\u0159\u00edklad \u0161kodliv\u00e9ho pesticidu pr\u00e1v\u011b glyfos\u00e1t, kter\u00fd z\u00a0hlediska toxicity, pokud v\u016fbec existuje, pat\u0159\u00ed ve srovn\u00e1n\u00ed t\u0159eba s\u00a0brodifakem nebo ofici\u00e1ln\u011b zak\u00e1zan\u00fdm karbofuranem k\u00a0t\u011bm v\u016fbec nejm\u00edrn\u011bj\u0161\u00edm.<\/p>\n","protected":false},"excerpt":{"rendered":" In the last issue of the journal VTEI (5\/2016), the reader can get acquainted with the opinion of SOVAK \u010cR to support “as soon as possible a complete ban on the use of glyphosate,” with regard to the possible contamination of surface waters with this substance (the main ingredient of total herbicides Roundup type) and its residues.<\/p>\n","protected":false},"author":8,"featured_media":936,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[2],"tags":[592,683,573,316],"coauthors":[30],"class_list":["post-2733","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-from-the-world-of-water-management","tag-glyphosate","tag-herbicides","tag-sovak-cr","tag-surface-water"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/2733","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/comments?post=2733"}],"version-history":[{"count":2,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/2733\/revisions"}],"predecessor-version":[{"id":30357,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/posts\/2733\/revisions\/30357"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/media\/936"}],"wp:attachment":[{"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/media?parent=2733"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/categories?post=2733"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/tags?post=2733"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.vtei.cz\/en\/wp-json\/wp\/v2\/coauthors?post=2733"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}