>>> we're back with robert costa, casey hunt and howard dean. robert i was saying that when jeb bush is talking about foreign policy, that team knows this is a weak spot for rand paul among republican primary voters. it is also a weak spot for mike huckabee among republican primary voters. so how much of this stepping into foreign policy was about exposing or going toward the weaknesses of the other candidates. >> bush is trying to signal to donors and to activists that though he doesn't have too much international experience he comes to this race as an unapologetic hawk. so it comes from the bush lineage on foreign policy. he's sending a message that though there is some pockets of the gop that are war weary, he's not going to be cowed by them and will stand by his traditional position. >> we have the latest poll out, a national poll of the republican candidates with mike huckabee at the top at 16%. jeb bush at 14%, rand paul 10%.

. >> reporter: senator robert casey says he has written a letter to the head o f.d.a. concerned about the dangers of powerederd caffeine a powerful supplement a single teaspoon of powdered caffeine is equal to 25 cups of coffee. >> teenagers, young adults are getting this powder because they want to lose weight they use it as a work out supplement. they are trying to study longer hours. >> reporter: it is easy to buy in has been link to two deaths. f.d.a. posted warnings to consumers on the web site outlining the dangers of powdered caffeine recommending the products be a avoided with you senator casey says the agency should be more aggressive and consider banning it the. >> reporter: why do you think it has hen f.d.a. so long to take action against this powdered caffeine. >> f.d.a. is a regulatory agency and sometimes may not have the same sense of urgency that we have or certainly that constituents or taxpayers have. >> reporter: powdered caffeine is milk with the liquid even small amounts can lead to an accidental overdose, rapid or eradic heartbeat is one of the ma

. >> reporter: pennsylvania senator robert casey joined by two leading infectious disease doctors, outlined dangers of measles and not being vaccinated. >> people are in the scared of the difficult ease but i'm scared of the disease because i lived through philadelphia a 1991 measles epidemic. >> reporter: doctor paul offit a nationally recognized vaccine expert say nine children died. newest one started in disney, california. it is now spread across the country but there is no evidence it is in our tri-state region. the is there concern here because pennsylvania has the secondlyes measles vaccination rate in the country. >> the national vaccination numbers a above 95 percent. pennsylvania unfortunately is above 86 percent. that is at last count. >> reporter: parents air loud to opt out of school vaccination requirements, some do for religious reasons. others feel they are potentially dangerous. >> think wye we are at tipping point. we have on one hand the individual rights to express their attitude and belief freely versus good have of society, and i think, in the end, it comes down to is

. >> pennsylvania senator robert casey says the fda should be more aggressive investigating powderedaffeine and consider banning it. >> why do you think it's taking the fda so long to take action. >> fda is a regulatory agency and sometimes may not have the same sense of urgency that we have or certainly that constituents are taxpayers have. >> it's not illegal and can be found online and in some stores. we went to vitamin so store in northeast philadelphia. the person selling it didn't know about the potential dangers. >> the fda is saying people probably shouldn't be using it. >> i'll have to tell the boss and maybe we'll do something about it and take the off the shelfs. >> everyone should be on the same page about how dangerous this substance is. and that should not be used in any form in any way. >> i call the fda for row action to senator casey. a spokesperson says the agency is considering every legal option and regulatory action consume mrs. are being advised to avoid powdered caffeines specially bulk bags sold on the internet. i'm instead of know stall, cbs3 "eyewitness news

. >> reporter: pennsylvania senator robert casey says the the f.d.a.hould be more aggressive investigating powerederd caffeine and consider banning it. why do you think it has taken the the f.d.a. so long to take action. >> the f.d.a. is a regulatory agency and sometimes may not have the same sense of urgency that we have for certainly that cop still wents or taxpayers have. >> reporter: it can be easily found on line and in some stores. we went to the vitamin store in northeast philadelphia. the the person selling it didn't know about the potential danger. >> the f.d.a. is saying that people probably shouldn't be using it. >> you'll have to tell the boss and maybe we will do something bit and take it off the the shelf. >> everyone should be on the same page about how dangerous this substance is and it should not be used in any form in anyway. >> reporter: i call for reaction to senator casey. a spokesperson says the the agency is considering every legal option and regulatory action. consumers are advised to avoid powdered caffeine especially bulk bags