{"id":1609,"date":"2017-10-01T00:00:09","date_gmt":"2017-10-01T00:00:09","guid":{"rendered":"https:\/\/himinn.fjarver.is\/mengunsjavar\/?p=1609"},"modified":"2024-09-09T10:14:21","modified_gmt":"2024-09-09T10:14:21","slug":"5-efnamengun","status":"publish","type":"post","link":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/2017\/10\/01\/5-efnamengun\/","title":{"rendered":"5. Efnamengun"},"content":{"rendered":"

5.1 Inngangur<\/h4>\n

Daglega berst miki\u00f0 magn efna \u00fat \u00ed umhverfi\u00f0. M\u00f6rg \u00feessara efna eru nau\u00f0synleg til a\u00f0 vi\u00f0halda l\u00edfi en \u00fdmis efni og efnasamb\u00f6nd geta einnig safnast fyrir, t\u00edmabundi\u00f0 e\u00f0a varanlega, og valdi\u00f0 mengun.<\/p>\n

Sum mengunarefni, eins og \u00feungm\u00e1lmar og n\u00e6ringarefni, eru upprunnin \u00ed n\u00e1tt\u00farunni. N\u00e1tt\u00farulegur styrkur \u00feeirra er breytilegur fr\u00e1 einum sta\u00f0 til annars og n\u00e1tengdur sta\u00f0bundnum umhverfisa\u00f0st\u00e6\u00f0um. Ve\u00f0run, rof og jar\u00f0hr\u00e6ringar valda \u00fev\u00ed a\u00f0 \u00feungm\u00e1lmar berast til sj\u00e1var. \u00deeir geta einnig borist \u00ed auknum m\u00e6li \u00fat \u00ed umhverfi\u00f0 vegna athafna manna (s.s. n\u00e1muvinnslu, ol\u00eduvinnslu, i\u00f0na\u00f0ar o.fl). N\u00e6ringarefni geta einnig borist \u00ed auknum m\u00e6li \u00fat \u00ed umhverfi\u00f0 af mannav\u00f6ldum (t.d. me\u00f0 afrennsli af landb\u00fana\u00f0arlandi, me\u00f0 fr\u00e1veitum o.fl.).<\/p>\n

\u00d6nnur mengunarefni eru mannger\u00f0 og finnast \u00fev\u00ed \u00ed umhverfinu eing\u00f6ngu fyrir tilstilli manna. H\u00e9r er um a\u00f0 r\u00e6\u00f0a t.d. l\u00edfr\u00e6n tinsamb\u00f6nd, \u00fer\u00e1virk l\u00edfr\u00e6n efni svo sem pl\u00e1guey\u00f0a sem nota\u00f0ir eru \u00ed landb\u00fana\u00f0i, eldvarnarefni og \u00fdmis efni sem notu\u00f0 eru \u00ed i\u00f0na\u00f0i og \u00ed neysluv\u00f6rur. \u00cd Evr\u00f3pu eru um 100.000 efni \u00e1 marka\u00f0i. Sum \u00feessara efna eru h\u00e6ttuleg vegna \u00feess a\u00f0 \u00feau eru \u00fer\u00e1virk, eitru\u00f0 og safnast fyrir \u00ed l\u00edfverum. Efni geta menga\u00f0 sj\u00f3inn me\u00f0 sl\u00e6mum aflei\u00f0ingum fyrir sj\u00e1varl\u00edfverur og jafnvel okkur mannf\u00f3lki\u00f0 \u00feegar vi\u00f0 neytum sj\u00e1varfangs.<\/p>\n

\"\"<\/a>

Mynd 5.1. Vinstra megin: \u00de\u00f6rungabl\u00f3mi \u00ed Eystrasalti vegna n\u00e6ringarefnaofau\u00f0gunar. H\u00e6gra megin: Mengunarefni upprunnin \u00ed i\u00f0na\u00f0i geta borist me\u00f0 loftstraumum og fr\u00e1veituvatni til sj\u00e1var.<\/p><\/div>\n

H\u00e6ttuleg efni finnast \u00ed sj\u00f3num, sj\u00e1varseti og sj\u00e1varl\u00edfverum um heim allan. N\u00e1l\u00e6gt \u00fe\u00e9ttb\u00fdlum sv\u00e6\u00f0um og i\u00f0na\u00f0arsv\u00e6\u00f0um getur styrkur h\u00e6ttulegra efna \u00ed seti og sj\u00e1varl\u00edfverum \u00f3gna\u00f0 l\u00edfr\u00edki sj\u00e1var og haft \u00fdmis l\u00edffr\u00e6\u00f0ileg \u00e1hrif. Mengun getur komist \u00e1 \u00fea\u00f0 stig a\u00f0 sj\u00e1varfang ver\u00f0i h\u00e6ttulegt heilsu f\u00f3lks, s\u00e9 \u00feess neytt.<\/p>\n

Tveir al\u00fej\u00f3\u00f0asamningar hafa veri\u00f0 sam\u00feykktir til a\u00f0 sporna vi\u00f0 mengun sj\u00e1var af v\u00f6ldum h\u00e6ttulegra efna \u00e1 okkar hafsv\u00e6\u00f0i, annars vegar MARPOL-samningurinn sem tekur \u00e1 losun fr\u00e1 skipum og hins vegar OSPAR-samningurinn sem er \u00e6tla\u00f0 a\u00f0 draga \u00far mengun fr\u00e1 uppsprettum \u00e1 landi, mengun af v\u00f6ldum varps<\/span> og brennslu \u00fargangs og mengun fr\u00e1 uppsprettum \u00e1 hafi (s.s. borp\u00f6llum), sj\u00e1 n\u00e1nar kafla 8.3<\/a>. S\u00fdnilegur \u00e1rangur hefur n\u00e1\u00f0st \u00ed a\u00f0 draga \u00far losun og styrkur flestra mengunarefna fer l\u00e6kkandi \u00ed Nor\u00f0ur-Atlantshafi en \u00fear sem m\u00f6rg efnanna eru h\u00e6ttuleg, \u00fer\u00e1virk og safnast fyrir \u00ed l\u00edfr\u00edkinu er mikilv\u00e6gt a\u00f0 fylgjast \u00e1fram vel me\u00f0 styrk \u00feeirra.<\/p>\n

\n

\"\"<\/a>\u00cd jan\u00faar 2016 fannst dau\u00f0ur h\u00e1hyrningur vi\u00f0 eyjuna Tiree vi\u00f0 Skotland. H\u00e1hyrningurinn hlaut nafni\u00f0 Lulu. Tali\u00f0 er a\u00f0 Lulu hafi drepist eftir a\u00f0 hafa fest sig \u00ed vei\u00f0arf\u00e6rum.\u00a0Sjaldan e\u00f0a aldrei hefur greinst eins miki\u00f0 magn af alls kyns eiturefnum \u00ed sj\u00e1varl\u00edfveru eins og greindust \u00ed Lulu. Styrkur PCB \u00ed fituvef Lulu var um 950 mg\/kg e\u00f0a meira en hundra\u00f0falt yfir \u00feeim styrk sem talinn er hafa \u00e1hrif \u00e1 heilsu sj\u00e1varspend\u00fdra.\u00a0Krufning leiddi \u00ed lj\u00f3s a\u00f0 Lulu haf\u00f0i aldrei eignast afkv\u00e6mi en PCB er einmitt tali\u00f0 hafa \u00e1hrif \u00e1 frj\u00f3semi.<\/p>\n

Hausti\u00f0 2013 syntu grindhvalir \u00e1 land \u00e1\"\"<\/a> Sn\u00e6fellsnesi. Nokku\u00f0 var um a\u00f0 f\u00f3lk f\u00e6ri \u00e1 sta\u00f0inn og n\u00e6\u00f0i s\u00e9r \u00ed bita. Matv\u00e6lastofnun og Emb\u00e6tti landl\u00e6knis v\u00f6ru\u00f0u \u00fe\u00f3 f\u00f3lk vi\u00f0 a\u00f0 leggja s\u00e9r kj\u00f6ti\u00f0 til munns. Kj\u00f6t grindhvala inniheldur miki\u00f0 magn kvikasilfurs og \u00fer\u00e1virkra l\u00edfr\u00e6nna efna \u00e1 bor\u00f0 vi\u00f0 d\u00edox\u00edn og PCB.<\/p>\n<\/div>\n

 <\/p>\n

Efnamengun \u00ed sj\u00f3num er \u00ed a\u00f0alatri\u00f0um tvenns konar. Annars vegar er um a\u00f0 r\u00e6\u00f0a n\u00e1tt\u00faruleg efni, \u00fe.e. efni sem finnast \u00ed n\u00e1tt\u00farunni en eru mengandi \u00feegar styrkur \u00feeirra \u00e1 \u00e1kve\u00f0num sta\u00f0 ver\u00f0ur meiri en n\u00e1tt\u00faran r\u00e6\u00f0ur vi\u00f0 – yfirleitt vegna athafna manna, \u00fe\u00f3 n\u00e1tt\u00farulegir atbur\u00f0ir (t.d. eldgos) geti einnig valdi\u00f0 mengun. H\u00e9r er t.d. \u00e1tt vi\u00f0 n\u00e6ringarefni sem eru nau\u00f0synleg til vaxtar og vi\u00f0halds l\u00edfvera en geta valdi\u00f0 ofau\u00f0gun og s\u00farefnisskorti ver\u00f0i styrkur \u00feeirra \u00ed umhverfinu of mikill. Enn fremur getur \u00feetta \u00e1tt vi\u00f0 um \u00feungm\u00e1lma. Hins vegar er um a\u00f0 r\u00e6\u00f0a mengun vegna mannger\u00f0ra efna. H\u00e9r \u00e1 eftir ver\u00f0ur fjalla\u00f0 n\u00e1nar um \u00ferenns konar mengun af v\u00f6ldum mismunandi efna: N\u00e6ringarefnaofau\u00f0gun, \u00feungm\u00e1lmamengun og mengun vegna mannger\u00f0ra efna, s\u00e9r \u00ed lagi \u00fer\u00e1virkra l\u00edfr\u00e6nna efna.<\/p>\n","protected":false},"excerpt":{"rendered":"

5.1 Inngangur Daglega berst miki\u00f0 magn efna \u00fat \u00ed umhverfi\u00f0. M\u00f6rg \u00feessara efna eru nau\u00f0synleg til a\u00f0 vi\u00f0halda l\u00edfi en \u00fdmis efni og efnasamb\u00f6nd geta einnig safnast fyrir, t\u00edmabundi\u00f0 e\u00f0a varanlega, og valdi\u00f0 mengun. Sum mengunarefni, eins og \u00feungm\u00e1lmar og Lesa meira…<\/a><\/p>\n","protected":false},"author":2,"featured_media":1749,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25],"tags":[],"class_list":["post-1609","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-5-efnamengun"],"_links":{"self":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/1609","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/comments?post=1609"}],"version-history":[{"count":45,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/1609\/revisions"}],"predecessor-version":[{"id":3947,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/posts\/1609\/revisions\/3947"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media\/1749"}],"wp:attachment":[{"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/media?parent=1609"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/categories?post=1609"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/himinnoghaf.is\/mengunsjavar\/index.php\/wp-json\/wp\/v2\/tags?post=1609"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}